THE  LIBRARY 

OF 

THE  UNIVERSITY 

OF  CALIFORNIA 

LOS  ANGELES 


GIFT 


/ 


UM^Co 


APPLIED  PRINCIPLES 


OF 


FIELD  FORTIFICATION 


FOR 


LINE    OFFICERS 


By  J.  A.  WOODRUFF, 

Captain,  Corps  of  Engineers,  U.S.A. 

Instructor,  Department  of  Engineering,  Army  Staff  College, 
Fort  Leavenworth,  Kansas. 

Formerly  Instructor,  Department  of  Civil  and  Military  Engineering. 
U.  S.  Military  Academy,  West  Point,  N.  Y. 


Adopted  by  Direction  of  the  Commandant  for  Use  in  the 
Service  Schools  at  Fort  Leavenworth. 

1909. 


Copyright,  1909, 
By  J.  A.  Woodruff. 


PRESS  OF  KETCHESON  PRINTING  CO., 
LEAVENWORTH,  KANSAS. 


U(? 


(J^6< 


PREFACE 


The  following  pages  are  written  with  the  idea  of  furnishing  the 
members  of  the  Army  School  of  the  Line  and  Staff  College  a  guide 
in  the  solution  of  field  problems  in  fortification.  These  problems 
are  such  that  any  line  officer  might  be  called  upon  to  solve  in  actual 
service.  Their  careful  solution  on  varied  terrain  in  time  of  peace 
will  give  an  officer  confidence  and  skill  in  their  solution  in  time  of 
war,  and  will  avoid  many  costly  delays  and  mistakes. 

It  is  intended  that  this  book  be  used  with  the  Engineer  Field 
Manual,  Part  V,  on  Field  Fortification,  so  that  most  of  the  details  of 
the  subject  contained  in  that  manual  are  omitted. 

The  author  desires  to  acknowledge  assistance  received  from 
Captain  Edwin  T.  Cole,  Sixth  Infantry,  Senior  Instructor;  Captain 
C.  O.  Sherrill,  Corps  of  Engineers;  and  First  Lieutenant  G.  C.  Mar- 
shall, Twenty-fourth  Infantry,  Instructors,  Department  of  Engineer- 
ing, Army  Service  Schools,  for  many  valuable  suggestions.  Also  to 
Sergeant  John  Howry,  First  Battalion  of  Engineers,  for  the  prepara- 
tion of  the  plates  herein. 

J.  A.  WOODRUFF, 
Captain,  Corps  of  Engineers,  U.  S.  A. 

Army  Service  Schools, 

Fort  Leavenworth,  Kansas, 
February  15,  1909. 


939598 


LIST  OF  BOOKS  CONSULTED. 


Engineer  Field  Manual,  Part  V War  Department. 

Field  Fortification Fiebeger. 

Field  Fortification  and  Field  Engineering L.  A.  Beach. 

Field  Fortification  Work  and  the  Present  Arma- 
ment   Clergerie. 

(Translated  from  the  French  by  Captain  W.  D.  Connor, 
Corps  of  Engineers.) 

Feldbefestigung V.  Brunner. 

Field  Service  Regulations War  Department. 

Fortification Clarke. 

Influence  of  the  Experience  of  the  Siege  of  Port 
Arthur   Upon   the    Construction   of    Modern 

Fortresses V.  Schwartz. 

(Translated  troni  the  Russian  in  the  M.  I.  D.  General 
Staff.) 

Letters  on  Applied  Tactics Griepenkerl. 

Notes  on  Field  Engineering  from  the  Diary  of  an 

Engineer  at  Port  Arthur Engineer  School. 

(Translated  from  the  Russian  in  the  M.  I.  D.  General 
Staff.) 

The  Principles  of  Land  Defense Thuillier. 

Reports  of  Military  Observers  Attached  to  the 
Armies  in  Manchuria  During  the  Russo-Japa- 
nese War ....  War  Department. 

A  Staff  Officer's  Scrap  Book Ian  Hamilton. 

Text  Book  of  Field  Engineering Phillips. 

War  in  Practice Baden  Powell. 


CONTENTS 


CHAPTER  I. 

GENERAL    PRINCIPLES. 

Page 

Type  designs  useless. —  Connection  between  fortification  and 
tactics. —  Tactical  aspects  of  fortification. —  Importance  of 
fortification. —  Classes  of  defensive  positions. —  An  intrenched 
camp. — A  defensive  line. — Advanced  positions. —  Second 
line. — Tactical  situation  of  the  works. —  Intervals. —  Mam 
roads. —  Form  of  supporting  points. —  Conditions  to  be  sought 
for  in  laying  out  or  constructing  works. —  Artillery  posi- 
tions.—  Precedence  of  infantry. —  Concealment  of  the  inte- 
rior of  the  defended  position. —  Command. —  Location  of 
works  in  second  line. —  Means  of  communication. —  Lines  of 
retreat  9 

CHAPTER  II. 

TACTICAL    ORGANIZATION    OF    INFANTRY    IN    DEFENSE. 

Division  into  sections. —  Strength  of  first  line,  supports  and  re- 
serves.—  Position  of  section  reserve. —  The  garrison  of  the 
points  of  support  of  the  second  line. —  General  reserve 27 

CHAPTER  III. 

TACTICAL    EMPLOYMENT    OF    ARTILLERY    IN    DEFENSE. 

Disposition  of  the  artillery. —  Mobility. —  Armament. —  Location 
of  the  emplacements. — Dispersion. — Position  with  reference 
to  the  infantry. — Location  of  guns. — Location  of  howitzers. — 
Indirect  fire  for  guns. —  Rapid  fire  guns. —  Field  guns. — 
Machine  guns 31 

CHAPTER  IV. 

DESIGN    OF    INFANTRY    WORKS. 

Designs  not  rigid.— General  objects  to  be  aimed  at. —  General 
character    of   supportmg    points. —  Redouts. —  Variation    in 


Page 
profiles. — Effect  of  weapons. — Profiles. — Head  cover. — Back- 
ground.— Arrangement  for  fire  to  the  rear.  —  Overhead  cover. 
Lookouts. —  Magazine  accomodations. —  Length  of  trenches. 
Location  of  trenches. —  Field  of  fire. —  Communication  with 
the  rear.— Cover  for  supports. — Drainage. —  Telephone  com- 
munication.—  Obstacles. —  Clearing  the  foreground. — Houses 
or  villages. — Woods. —  Concealment. —  Dummy  trenches  or 
parapets 37 

CHAPTER  V. 

ARTILLERY    POSITIONS. 

Low  command  and  concealment. —  Form  of  emplacement. — Posi- 
tions for  light  guns. —  Indirect  fire. —  Expense  magazines. — 
Means  of  access. —  Observing  stations. —  Use  of  balloons. — 
Emplacement  for  machine  guns 76 

CHAPTER  VL 

AUXILIARY    MEANS    OF    DEFENSE. 

Electric   searchlights. —  Interior   communications. —  Telegraphic 

and  Telephonic  communication. — Water  supply 85 

CHAPTER  VII. 

STRENGTH    OF    GARRISON. 

Determining  considerations. —  Hasty  occupation  of  a  position. — 
More  deliberate  occupation. — An  elaborately  prepared  posi- 
tion.—  Strength  of  infantry. —  Artillery. —  General  reserve. — 
Examples •. 88 

CHAPTER  VIII. 

DEFENSE   OF    SMALL    ISOLATED    POSTS    OCCUPIED    BY    DETACHMENTS. 

Modification  necessary. — A  very  small  position. — Form  of  works. 
All-around  defense. —  Position  of  works. — Enemy  uncivilized 
or  unprovided  with  artillery 92 

CHAPTER  IX. 

FORTIFICATIONS    ON    THE    OFFENSIVE. 

General  ch  iracter. — Fortifications  on  the  battlefield. — Location. — 

Tactical  intrenchments. —  Siege  operations 95 


CHAPTER  X. 

CALCULATION  OF  TIME  AND  MEN  REQUIRED  TO  EXECUTE  DEFENSIVE 

WORKS. 

Page 

Tasks. —  Double  gangs. —  Traction  ditchers. —  Redouts. — Firing 

trenches. —  Overhead    cover. —  Communicating    trenches, — 

Gun  pit. — Observmg  station. — Machine  gun  emplacement. — 

Table 100 

CHAPTER  XI. 

FIELD    PROBLEMS    IN    FORTIFICATION. 

Relation  to  terrain  exercises. —  Staff  class  course. —  Chief  value. — 
General  instructions. —  Advanced  method. —  Three  prob- 
lems with  solutions 105 


APPENDIX. 
Tools  carried  by  the  different  arms 127 


APPLIED   PRINCIPLES 


-OF- 


FIELD    FORTIFICATION 

FOR  LINE  OFFICERS. 


CHAPTER  I. 
General  Principles. 

1.  In  the  following  discussion  no  attempt  will  be 
made  to  lay  down  rules  or  to  establish  typical  forms  of 
works  that  will  be  suitable  to  all  circumstances.  It 
should  be  remembered  that  the  true  essentials  of  a  forti- 
fied position  cannot  be  expressed  on  plans  and  maps. 
The  disposition  and  the  design  of  the  defensive  works 
should  be  decided  on  the  actual  ground  to  be  defended, 
and  only  after  a  full  consideration  of  the  tactical 
circumstances.  As  the  tactical  considerations  will  vary 
greatly  in  different  cases,  it  would  be  impossible,  even 
if  it  were  advisable,  to  lay  down  any  system  which  would 
be  applicable  to  all.  Even  the  design  of  the  individual 
works  depends  solely  on  the  tactical  considerations.  Type 
designs  are  therefore  useless,  except  as  a  general  guide. 

2.  Fortification  is  intimately  connected  zvith  Tactics, 
so  much  so  that  it  would  hardly  be  too  much  to  say  that 
Fortification  is  itself  but  a  special  branch  of  Tactics  and 
not  a  separate  division  of  the  Military  Art.  Though 
the  purely  technical  parts  of  the  subject  are  assigned  to 
the  Engineers,  yet  a  knowledge  of  the  correct  tactical 


10 

disposition    and    employment    of    defensive    works    is    a 
necessity  for  every  soldier. 

3.  The  tactical  aspect  of  Fortification  lies  in  its  adap- 
tation to  the  natural  features  of  the  ground  and  to  the 
nature  of  the  weapons  employed  by  either  side;  tactical 
considerations,  based  principally  on  the  above,  but  also 
on  the  probable  direction,  nature,  strength,  and  other 
conditions  of  the  expected  attack,  will  govern  the  general 
dispositions  of  the  defensive  measures,  the  strength  of 
the  garrison  and  the  armament  required. 

4.  It  is  the  history  of  all  modern  wars  that  the  men 
do  not  take  kindly  to  the  spade,  and  it  is  only  through 
bitter  experience  that  they  learn  the  value  of  intrench- 
ments.  Every  effort  should  be  made,  therefore,  by  the 
officers  to  impress  this  fact  upon  their  men  and,  if  pos- 
sible, teach  them  the  lesson  at  the  outset,  and  before  the 
enemy  has  the  opportunity  of  doing  so  in  a  more  forceful 
and  costly  manner. 

Major  Carl  Reichmann,  in  his  report  on  the  Russo- 
Japanese  War,  states :  "It  may  be  truthfully  said  of  the 
Russians,  and  probably  of  the  Japanese  also,  that  when 
they  did  not  march  or  fight  they  dug." 

Major  J.  F.  Morrison  states :  "Great  reliance  was 
placed  on  field  intrenchments,  and  their  use  was  very 
general.  Once  in  the  presence  of  the  enemy  the  intrench- 
ing tool  seemed  next  in  importance  to  the  rifle  and 
ammunition.  The  rule  on  both  sides  seemed  to  be  to 
always  cover  their  positions  with  intrenchments  as  soon 
as  taken  up,  even  when  held  only  for  a  short  time." 

5.  Classes  of  Defensive  Positions. — Defensive  posi- 
tions may  vary  from  the  great  extensive  fortified  position 
guarding  some  important  city  or  strategic  point  liable  to 


11 

be  assailed  by  a  formidable  force  and  therefore  requir- 
ing an  army  for  its  defense,  to  a  small  fortified  post 
holding  a  road,  a  pass  or  a  bridge  head,  and  occupied  by 
a  small  detachment. 

Again,  the  methods  of  defense  vary  according  to  the 
weapons  that  may  be  used  by  the  expected  attacking 
force,  and  many  of  the  measures  that  would  be  neces- 
sary against  a  force  employing  siege  guns,  howitzers  and 
mortars  would  be  unnecessary  against  a  force  with  field 
guns  alone,  or  without  any  artillery. 

When  troops  occupy  a  defensive  position  for  a  con- 
siderable length  of  time,  the  field  fortifications  thrown 
up  hastily  at  the  beginning  of  the  period  will,  by  an 
energetic  commander,  be  increased  in  strength  until  they 
attain  a  resisting"  power  approximating  tliat  of  perma- 
nent fortifications. 

The  position  may  be  prepared :  first,  as  a  line  bar- 
ring advance  along  some  natural  line  of  operations ; 
second,  to  surround  some  important  nucleus  whicli  it  has 
been  determined  to  hold  as  long  as  possible. 

A  position  of  the  first  class  will  be  held  by  the  defend- 
ing force  as  long  as  may  be  done  without  subjecting  it 
to  being  surrounded  and  ultimately  captured.  The  posi- 
tion of  the  Russians  at  Liaoyang  and  on  the  Sha  River 
are  illustrative  of  this  class. 

In  the  positions  of  the  second  class,  the  intention  is 
to  hold  tEe' position  for  as  long  a  time  as  possible,  and 
this  usually  involves  the  sacrifice  of  the  defending  force. 
SucTr  pDsiridns  are  usually  occupied  by  permanent  forti- 
fications, often  supplemented  by  field  works,  as  at  Port 
Arthur.  But  examples  in  field  fortification  may  be  found 
in  Plevna,  Vicksburg,  Petersburg  and  Sebastopol. 

Any  field  army  may  therefore  be  called  up  to  defend 


12 

a  fortified  position,  and  such  operation  may  include  all 
the  refinements  of  regular  sieg;e  operations. 

Major  J.  E.  Kuhn  states :  "I  am  of  the  opinion  that 
a  defensive  position  properly  prepared  and  skilfully 
adapted  to  the  ground  will  impose  upon  the  attack  meth- 
ods analogous  to  those  employed  in  sieges,  and  this 
without  recourse  to  any  very  elaborate  works  of  con- 
struction." 

6.  A^v_Jntrenched  camp  or  an  all-around  defensive 
position  would  consist  at  the  present  day  of  a  series  of 
fortified  and  strongly  held  positions  surrounding  the  town 
or  other  object  to  be  defended,  and  so  situated  in  tactical 
relation  to  each  other  that  it  would  be  impossible  for  an 
attacker  to  penetrate  to  the  interior  of  the  defensive  line 
without  first  capturing  some  of  these  positions. 

The  distance  of  the  defensive  line  from  the  nucleus 
would  in  almost  all  cases  be  decided  by  the  topography, 
but  this  line  should  be  so  selected  as  to  prevent  the 
enemy  from  locating  any  batteries  within  a  range  less 
than  10.000  yards  from  the  nucleus,  if  aimed  and  ob- 
served fire  is  possible  from  the  location. 

Sometimes  it  will  be  sufficient  to  keep  the  enemy's 
position  out  of  sight  of  the  town,  as  unaimed  and  unob- 
served fire  will  seldom  be  effective,  and  it  may  happen 
that  a  conveniently  intervening  range  of  hills  would 
effect  this;  it  should,  however,  be  remembered  that  ob- 
servation of  fire  can  be  conducted  with  sufficient  accuracy 
to  hit  a  town  or  other  large  area  from  captive  balloons, 
so  the  end  would  not  be  achieved  if  the  town  could  be 
seen  from  balloons  sent  up  from  the  besieger's  positions, 
if  the  latter  were  within  range. 

It  will  seldom  be  wise  in  the  case  of  a  large  and  im- 
portant town  to  rely  on  a  single  line  of  fortified  positions 


13 

for  its  defense.  Therefore,  it  is  often  desirable  to  keep 
the  main  defensive  line  at  a  considerable  distance  from 
the  nucleus  in  order  to  leave  room  for  a  second  line  or 
retired  position,  in  case  some  of  the  works  in  the  front 
line  are  captured. 

7.  A  Defensive  Line. — The  above  principles  apply 
equally  to  cases  where  the  position  is  a  straight  line  or 
an  arc  with  secured  flanks.  It  is  imperative,  however,  in 
such  cases  that  the  flanks  cannot  be  turned. 

The  defensive  organization  of  the  flanks  of  any  posi- 
tion merits  special  attention  not  only  because  the  best 
location  for  the  troops  that  cannot  be  made  use  of  in 
the  fortifications  themselves  will  be  in  outflanking  eche- 
lons in  rear,  but  also  because  this'  disposition,  for  the 
points  of  support  on  the  flanks,  must  be  adopted  in  pref- 
erence to  a  break  to  the  rear  in  the  general  line  of 
defense.  It  moreover  favors  counter  attacks  upon  the 
flank  of  the  adversary  and  renders  much  more  eas}^  the 
execution  of  these  outflanking  movem.ents  whose  object 
is  to  envelop  the  enemy's  wings. 

8.  Advanced  positions  in  front  of  the  main  line  of 
defense  often  are  of  considerable  value  in  delaying  the 
besieger's  progress  and  prolonging  the  defense.  They 
form  good  pivots  for  the  outpost  line ;  they  force  the  be- 
siegers to  deploy  or  to  commence  their  siege  works  at 
a  much  greater  distance  from  the  place;  they  may  even 
possibly  necessitate  a  regular  formal  attack  being  under- 
taken against  themselves,  before  the  besieger  can  turn 
his  attention  to  the  main  works.  They  cause,  in  fact, 
delay,  which  is  of  priceless  value  in  a  siege. 

They  should  be  selected  so  as  to  necessarily  force 
the  besiegers  to  stay  their  advance  till  they  are  taken. 


14 

They  should  be  proof  against  assauh  over  the  open,  and 
the  communications  to  them  from  the  main  position 
should  be  secure  and  hidden,  so  that  it  is  possible  to 
reinforce  them  or  withdraw  their  garrisons  unseen.  The 
positions  should  be  commanded  by  the  artillery  and  the 
infantry  positions  of  the  main  line,  so  as  to  deny  their 
use  to  the  enemy  after  they  have  been  vacated;  and  the 
works  constructed  on  them  should  be  of  such  a  nature 
as  to  give  no  cover  to  the  enemy. 

Placed  so  as  to  easily  overlook  the  approaches  to  the 
position,  these  points  of  support  will  frequently  occupy 
the  military  crest  or  some  similar  position:  but  they  must 
be  chosen  and  organized  so  as  to  allow  no  part  of  them 
to  be  seen  by  the  enemy  from  a  distance. 

The  points  of  support  of  the  advanced  line  must, 
moreover,  satisfy  as  far  as  possible  the  condition  of  per- 
mitting an  easy  retreat.  The  latter  should  be  prepared 
so  as  not  to  incommode  the  action  of  the  line  in  rear, 
which  constitutes  the  main  or  principal  line  of  combat. 

The  advanced  line  will  not  always  exist,  but  it  will 
often  be  useful  and  possible  to  construct  one,  and  the 
use  of  it  will  certainly  be  more  frecjuent  in  the  future 
than  it  has  been  in  the  past.  When  it  does  exist  the 
resistance  that  it  will  furnish  ought  to  be  sustained  as 
long  as  possible,  so  as  to  make  the  enemy  believe  that 
he  is  already  in  front  of  the  main  line,  and  to  cause  the 
attack  to  make  great  preparations  to  carry  this  line,  and 
perhaps  to  make  him  attempt  a  decisive  attack  and  thus 
make  a  useless  attack,  which  will  result  in  his  arriving- 
in  a  most  critical  condition  in  front  of  the  main  line. 

It  may  occasionally  happen  that  a  point  exists  in  front 
of  the  defensive  line  which  would  afford  a  very  com- 
manding position  at  short  range  for  the  enemy,  and  which 


/ 

15 

therefore  must  be  occupied  and  held  at  all  costs.  This 
case  is  different  from  that  of  an  ordinary  advanced  work 
which  it  is  intended  to  vacate  ultimately.  Such  a  post 
must  be  made  as  strong  and  secure  as  possible,  and  the 
defenders  must  be  given  to  understand  that  they  have 
to  hold  out  to  the  last.  If  covered  communications  can- 
not be  provided,  reliefs,  supplies,  etc..  must  be  carried  up 
at  night  only. 

9.  Second  Line. — The  object  of  the  second  line  is, 
in  the  event  of.  one  of  the  positions  in  the  main  line 
having  been  captured,  to  oppose  a  bar  to  the  further 
advance  of  tlie  besiegers.  Also  these  retired  works  will 
form  pivots  for  the  action  of  the  general  reserve,  in  the 
event  of  any  of  the  besieger's  troops  penetrating  the 
front  line  by  any  means. 

The  second  lin^  must  not  be  commanded  by  the  first, 
for  in  case  a  portion  of  the  first  line  were  captured,  the 
attackers  would  be  able  to  render  the  works  of  the  sec- 
ond line  untenalile.  It  must  be  placed  so  that  it  is  not 
subjected  to  the  fire  of  an  attack  which  is  made  upon  the 
main  line ;  it  must  be  near  enough  to  immediately  receive 
the  assailant  under  its  fire  as  he  starts  to  attack  it.  It 
will  therefore  ha\e  to  be  in  a  good  position,  if  such  a 
one  can  be  found,  _abgu^  500  or  600  yards  _behind  the 
first  line. 

The  works  should,  if  possible,  be  arranged  so  as  to 
bring  a  heavy  fire  upon  the  rear  of  the  works  in  the 
front  line  in  the  event  of  their  being  captured ;  also  so 
that  the  attackers  cannot  make  a  dash  between  them 
upon  the  town  or  place  defended.  A  continuous  enciente 
is  totally  unsuitable.  Detached  works  or  groups  of  works 
on  tactical  points  are  infinitely  better,  and  it  will  often 
be  found  that  one  powerful  group  of  works  on  a  com- 


16 

manding  but  retired  position  will  successfully  dominate 
a  large  section  of  the  defensive  area.  For  their  general 
disposition  and  design,  the  descriptions  given  in  the  case 
of  the  main  works  apph^  equally  well,  except  that  as  a 
general  rule  they  need  not  be  so  strong,  and  in  many 
cases  concealment  will  not  be  so  necessary. 

10.  Tactical  Situation  of  the  Works. — There  are 
three  prime  conditions  to  which  every  defensive  position 
should  conform : 

1.  It  should  admit  of  full  scope  for  the  effective  use 
of  the  defender's  weapons. 

2.  It  should  restrict,  as  far  as  possible,  the  effect  of 
the  attacker's  weapons. 

3.  It  should  provide  full  facilities  for  tactical  con- 
trol and  movement  of  the  defender's  forces. 

If  a  hill  or  other  commanding  feature  be  occupied 
by  some  of  the  defender's  troops  in  such  a  manner  that 
they  can  sweep  with  the  fire  of  their  weapons  the  ground 
in  front  and  on  both  flanks  of  it,  then  none  of  the  at- 
tacker's troops  can  pass  by  that  position  within  the  limits 
of  effective  range  of  the  weapons  of  the  troops  holding 
it.  If  the  defenders  hold  two  such  positions  situated  at 
such  a  distance  apart  that  the  occupants  can  sweep  with 
their  fire  the  whole  of  the  ground  between  them,  then 
the  enemy  would  be  unable  to  pass  between  the  two,  or 
within  effective  range  of  their  outer  flanks. 

A  series  of  positions  all  around  the  town  arranged  in 
the  above  manner,  so  that  the  ground  between  every  pair 
can  be  swept  by  rifle  fire  from  the  works,  or  artillery  fire 
in  rear,  would  make  it  impossible  for  the  enemy  to  pene- 
trate without  capturing  one  or  more  of  the  fortified  posi- 
tions. 


17 

The  organization  of  a  defensive  field  of  battle  includes 
the  utilization  of  natural  points  of  support,  such  as 
woods,  villages  and  forests,  and  the  creation  of  artificial 
points  of  support.  The  necessity  of  establishing  con 
nection  between  the  action  of  the  various  points  o^ 
support  over  the  entire  extent  of  a  defensive  positior 
does  not  always  permit  the  choice  of  the  most  favoraLe 
site  for  each  of  them,  but  nevertheless,  since  there  is 
considerable  latitude  in  the  location  of  the  whole  posi- 
tion and  as  the  location  of  the  interpolated  works  can 
often  be  varied  within  certain  limits,  it  is  well  to  state 
the  advantages  that  are  given  to  each  point  of  support 
oy  the  position  that  it  occupies  upon  the  ground.  (See 
paragraphs  18  and  53.) 

11.  The  intervals  between  the  supporting  points 
would  not  necessarily  be  all  the  same.  Where-the  g^-ound 
in  the  intervals  is  absolutely  open  and  flat  it  might  extend 
up  to  2,000  to  2,500  yards;  where  it  is  le^  favorable  it 
might  be  necessary  to  make  jt  only  1^^000  yards  or  even 
less.  If  the  ground  is  very  broken,  so  that  there  is  much 
space  concealed  from  view  from  either  of  the  adjoining 
works,  subsidiary  works  or  trenches  might  be  necessary 
in  the  intervals  to  cover  the  dead  ground.  On  the  other 
hand,  these  intervals  may  evidently  be  increased  when 
the  terrain  can  be  covered  both  in  front  and  on  the  flanks 
by  a  fire  of  artillery. 

12.  All  main  roads  or  other  lines  of  approach  by 
which  an  attacker's  columns  would  probably  advance 
should  be  covered  by  the  fire  of  positions  such  as  the 
above.  Machine  guns  and  artillery  should  also  be  placed 
so  as  to  sweep  them. 

13.  Form  of  Supporting  Points. — It  is  now  neces- 


sary  to  consider  what  will  be  the  form  of  the  supporting 
points  above  mentioned.  Anything  in  the  nature  of  a 
fort  or  redout  must  always  form  a  more  or  less  con- 
spicuous target,  and  be  certain  of  receiving  a  heavy  an«f. 
concentrated  fire  from  the  besieger's  batteries.  The  in- 
terior  of  a  redout  will  necessarily  be  somewhat  crowded, 
and  heavy  explosive  shells  dropped  into  crowded  re- 
stricted spaces  are  known  to  have  a  most  destructive 
effect.     (See  paragraph  42.) 

It  is  quite  possible,  on  account  of  the  greatly  increased 
defensive  power  of  the  rifles  of  the  present  day,  to  space 
the  defenders  of  a  line  of  parapet  at  much  greater  dis- 
tances apart  than  was  the  rule  in  past  times.  A  line 
of  men  with  magazine  rifles,  four  to  six  paces  apart, 
behind  good  cover,  can  bring  such  a  hail  of  bullets 
over  the  open  ground  in  their  front  to  a  considerable 
distance  from  their  own  position  as  to  effect  terrible 
loss  on  any  troops  endeavoring  to  advance  on  it. 
Such  dispersion,  moreover,  is  advantageous  in  that  it 
reduces  the  risk  of  casualties  from  the  hostile  fire,  and 
in  an  immovable  defensive  position  cannot  be  con- 
sidered too  great  for  effective  supervision  and  control. 
(See  Chapter  VII.  and  the  last  part  of  paragraph  45.) 

It  seems  probable,  therefore,  that  each  of  the  detached 
points  that  go  to  make  up  a  great  defensive  position 
would  consist  merely  of  a  locality  or  tract  of  ground  ren- 
dered defensible  by  a  skilful  treatment  of  its  natural  feat- 
ures; that  is  to  say,  by  the  provision  of  simple  trenches 
or  jg^rapets,  in  such  a  manner  as  to  interfere  as  little 
as  possible  with  the  natural  appearance  of  the  ground. 

The  organization  to  be  given  to  a  point  of  support 
depends  upon  the  tactical  circumstances  of  the  moment, 
upon  the  number  of  men  that  must  defend  it,  upon  the 


19 

role  that  it  must  play  in  the  action  as  a  whole,  upon  the 
subdivision  that  the  commander  of  the  defense  intends 
to  make  of  his  forces  between  the  garrison  of  the  works 
which  will  form  the  fixed  line,  and  the  maneuvering 
troops,  and  upon  the  manner  in  which  he  intends  to 
employ  these  last-named  troops. 

Major  W.  V.  Judson,  in  his  report  on  the  Russo- 
Japanese  War,  states:  "A  fortified  line,  whether  its 
plan  be  a  closed  figure  embracing  a  city,  or  a  straight 
or  broken  line  marking  the  front  of  an  army,  should 
be  marked  by  the  absence  of  local  and  congested  defen- 
sive units,  which  would  simply  form  satisfactory  targets 
for  the  enemy's  artillery. 

"Troops  will  and  should  be  trained  with  great  care 
in  night  marching  and  night  attack.  The  difficulties  for- 
merly dwelt  upon  in  connection  with  night  attacks  may 
be  overcome  by  careful  practice.  Drill  regulations  should 
treat  especially  of  methods  and  formations  for  conduct- 
ing such  operations. 

"Now,  the  effect  of  this  certainty  of  night  attack  is 
to  render  insecure  the  defense  of  intervals  between  works 
or  between  fortified  pi\-ots.  The  properly  fortified  line 
then  becomes  continuous.  Individual  works  are  ordin- 
arily  but  short  trenches^ conforming  to  the  ground.  These 
short  trenches  are  not  in  a  continuous  line  parallel  to  the 
front,  but  occupy  what  may  be  called  a  defensive  belt,  of 
a  widtHjvarying  between  200  or  300  yards  and  half  a 
mile,  depending  upon  the  ground  and  the  importance  of 
the  sector.  Each  of  the  small  units  is  of  the  least  pos- 
sible depth  (extension  in  the  line  of  fire).  Many  should 
be  provided  with  bomb-proofs.  Some  should  be  designed 
for  fire  either  to  front  or  rear.  Trenches  subject  to 
enfilading  fire  should  be  of  short  length  or  broken  and 


20 

well  traversed.  Deep  covered  communications,  either 
zigzagged  or  traversed,  should  be  multiplied  within  th's 
belt,  and  connect  the  works  with  the  naturally  or  artifi- 
cially protected  places  for  the  supports.  Two  to  four 
miles  inside  the  belt,  approximately  parallel  thereto,  but 
concealed  wherever  possible  by  the  folds  of  the  ground 
or  by  vegetation,  should  be  a  road  as  well  built  as  pos- 
sible, of  a  width  up  to  60  or  80  feet  for  grand  positions. 
Along  the  road  are  situated  the  headquarters  of  larger 
units,  most  of  the  reserves  and  depots  of  ammunitions, 
food  supply,  etc.  From  this  great  road,  which  would 
often  be  paralleled  by  rails,  should  branch  out  fan-shaped, 
a  system  of  narrower  roads  connecting  it  with  the  sup- 
ports behind  the  belt.  These  roads,  especially  toward  the 
front,  should  be  located  with  the  greatest  care  to  secure 
concealment,  and,  in  places,  might  have  to  be  sunken  or 
traversed. 

"It  has  been  held  that  ease  of  command  and  control 
would  be  sacrificed  if  a  fortified  line  were  of  the  char- 
acter advocated  herein.  This  is  true  io  :i  certain  extent, 
just  as  command  and  control  are  sacrificed  when  the  skir- 
mish line  is  used.  But  in  the  case  of  tlie  fortified  line  a 
sufficient  installation  of  telephones  vVill  tend  to  remedy 
the  evil.  The  Russians  had  four  or  five  telephones  to  the 
mile,  along  the  fortified  belt,  in  addition  to  many  behind 
it,  and  in  addition  to  telephones  for  fire  direction  of  ar- 
tillery. 

"With  three  or  four  thousand  men  to  the  mile  of 
front,  including  all  reserves,  a  fortified  line  of  the  belt 
type  is  invulnerable  to  frontal  attack.  It  cannot  be 
shaken  by  artillery  fire,  as  the  troops  are  protected  against 
shrapnel,  while  the  chances  of  hits  by  explosive  shells  are 


21 

exceedingly  small,  and  the  results  of  such  hits  are  not 
serious." 

14.  The  conditions  that  should  be  sought  for  in 
laying  out  or  constructing  these  trenches  or  parapets 
should  be,  as  in  all  other  defensive  works : 

1.  A  good  field  of  fire  over  all  the  ground  over 
which  the  enemy  could  advance. 

2.  As  great  a  measure  of  invisibility  as  it  would  be 
possible  to  obtain  under  the  local  conditions. 

3.  Good  cover  from  rifle  and  ordinary  artillery  fire 

4.  Good  covered  and  concealed  means  of  communi- 
cation with  all  parts  of  the  position. 

15.  Artillery  Positions. — The  guns  of  the  defense 
should  be  placed  in  such  situation  as  would  afford  the 
greatest  scope  for  their  fire,  combined  with  as  great 
a  measure  of  invisibility  as  the  circumstances  will  admit 
of,  and  also  with  the  power  of  unobserved  removal  and 
bringing  up.  They  need  not  necessarily  be  clear  of  the 
infantry  portions  of  the  fortified  positions,  for  the  con- 
ditions are  very  different  from  those  which  prevailed  in 
the  confined  forts  of  the  old  type.  In  extended  positions 
of  the  type  above  described,  it  would  not  be  difficult  to 
find  for  the  guns  sites  so  placed  that  they  would  not  draw 
on  the  infantry  trenches  the  hostile  artillery  fire.  It 
might  often  be  that  the  best  sites  would  be  on  the  flanks 
of  the  infantry,  but  it  is  not  necessarily  so,  and  they 
might  sometimes  be  placed  so  as  to  fire  over  them.  (See 
Chapter  V   and  paragraph  18.) 

Major  Kuhn  states:  "The  Japanese  showed  great 
attention  to  the  subject  of  concealment  in  selecting  their 
gun  positions;  much  of  the  firing  was  mdirect.     Where 


22 

no  natural  concealment  existed,  artificial  concealment  was 
provided,  if  possible. 

"The  artillery  positions  shonld,  wherever  possible,  be 
located  at  some  little  distance  to  the  rear  or  flank  of  the 
infantry  trenches  and  at  a  safe  distance  from  positions 
of  supports,  reserves,  magazines,  or  anything  else  which 
one  desires  to  protect  from  hostile  fire.  High  angle 
fire  is  a  little  wild  at  the  best,  while  direct  fire  gives  a 
large  danger  zone  to  the  rear  from  ricochet  shots. 
Anything  near  the  artillery  positions  will  come  in  for 
a  good  bit  of  exposure  from  fire  directed  at  the  artillery, 
hence  the  importance  of  keeping  the  latter  somewhat  sep- 
arated from  other  elements  of  the  defense." 

16.  Precedence  of  Infantry. — If  there  is  any  ques- 
tion as  to  whether  guns  or  infantry  shall  occupy  any 
particular  site,  the  way  to  settle  it  is  to  consider,  not 
which  arm  is  most  suited  for,  but  which  form  of  fire  it 
is  important  to  have  at  that  particular  point.  Generally 
it  will  be  found  that  infantry  fire  is  the  more  essential, 
for  it  must  always  be  remembered  that  rifle  fire  forms 
the  bedrock  of  all  defense,  and  that  artillery  fire  is  but 
an  accessory — a  highly  important  one,  but  still  never 
more  than  an  accessory.  It  will  generally  also  be  found 
possible  to  find  another  site  for  guns  from  which  the 
same,  or  nearly  the  same,  effect  can  be  produced,  as  from 
the  point  in  ciuestion,  while  it  may  sometimes  be  dan- 
gerous to  leave  it  without  infantry  defense. 

17.  Concealment  of  the  Interior  of  the  Defended 
Position. — It  is  of  great  advantage  if  the  main  defensive 
line  can  have  the  ground  steeply  sloping  away  from  it  in 
its  immediate  rear.  Not  only  would  such  a  conforma- 
tion make  it  easy  to  provide  cover  for  local  reserves  and 
for  the  defender's  encampments,  but   it   would  conceal 


23 

from  the  enemy's  view  all  that  went  on  within  the  de- 
fender's lines.  The  latter  condition  is  of  infinite  value 
and  worth  many  sacrifices  to  obtain.  At  all  events  the 
general  position  taken  up  should,  if  possible,  be  one  that 
admits  of  situations  being  found  out  of  view  of  the 
enemy  for  the  camping  grounds  of  the  defending  troops ; 
and  also  of  the  communications  being  concealed.  If  the 
latter  cannot  be  achieved  by  natural  means,  it  should 
by  artificial. 

18.  Command. — It  is  generally  considered  very  ad- 
vantageous to  place  the  defending  works,  if  possible,  on 
commanding  heights.  It  is  doubtful,  however,  whether 
beyond  a  certain  point  this  is  an  advantage.  Infantry 
fire  with  the  low  trajectory  rifles  of  the  present  day  is 
less  effective  from  a  height  than  from  a  low  site.  It  is 
best  to  as  near  as  possible  graze  the  surface  of  the  ground 
over  which  the  attackers  must  advance.  The  same  argu- 
ment applies  to  the  fire  of  low-trajectory,  high-velocity 
guns;  with  these  ag^ainst  troops  in  the  open  it  is  desirable 
to  burst  the  shrapnel  with  as  flat  or  grazing  a  trajectory 
as  possible.  For  fire,  either  of  guns  or  howitzers  against 
works,  an  elevated  position  gives  better  searching  effect, 
but  at  longe  range  this  does  not  make  so  much  difference 
as  is  generally  supposed.  A  high  site  for  a  defensive 
position  has  also  certain  positive  disadvantages.  Hardly 
any  hillsides  are  at  a  uniform  glacis-like  slope  all  the 
way  up.  If  they  are  convex  in  section,  it  is  impossible 
to  avoid  having  a  good  deal  of  hillside  and  ground  at 
the  foot  hidden  from  the  defender's  positions,  and  there- 
fore the  attackers  can  advance  up  it  unseen  and  un- 
harmed. If  it  is  concave,  then  to  be  able  to  see  and  fire 
all  down  the  slope,  the  defenders  are  obliged  to  expose 
themselves  greatly  to  direct  fire.     Moreover,  on  an  ele- 


vated  position  the  attacker's  artillery  can  safely  keep  up 
a  heavy  fire  over  the  heads  of  their  advancing  infantry 
till  the  very  last  moment. 

Elevated  positions  derive  a  certain  amount  of  ad- 
vantage from  the  fact  that  it  is  less  easy  for  the  works 
to  be  searched  out  by  the  fire  of  the  attacker's  artillery. 
But  well-concealed,  narrow,  trench-like  works  have  in 
any  case  little  to  fear  from  this  form  of  fire.  A  more 
positive  advantage  is  found  in  the  fact  that  elevated  po- 
sitions, such  as  those  on  ridges,  lines  of  hills,  etc.,  will 
nearly  always  give  concealment  from  the  enemy's  view  to 
the  interior  of  the  defended  area.  Similarly  such  posi- 
tions permit  of  a  range  of  view  over  the  attacker's 
positions  and  enable  the  defenders  to  note  his  movements. 
Observation  of  artillery  fire  is  also  more  accurately  car- 
ried out  from  elevated  positions. 

For  these  last  reasons,  therefore,  it  is  desirable  for  a 
defensive  position  to  have  a  certain  amount  of  command 
over  the  ground  over  which  the  enemy  must  advance. 
The  actual  height,  however,  need  only  be  sufficient  to 
give  a  good  view  over  the  ground  in  front,  particularly 
to  clear  all  obstacles  to  vision,  such  as  crops,  trees,  under- 
growth, etc.,  and  also  to  obtain  concealment  for  the  in- 
terior of  the  defender's  lines.  With  flat,  open  country 
it  may  be  very  little  indeed.  The  slopes  to  the  front 
should  be  as  gentle  and  evenly  sloping  as  possible. 

Major  Kuhn  states :  ''From  what  I  saw  in  Man- 
churia, I  was  strongly  impressed  by  the  fact  that  the 
disadvantages  of  a  commanding  position  often,  and  gen- 
erally, outweigh  the  advantages." 

In  commenting  on  the  location  of  the  Russian  defenses 
on  the  highest  ridges  and  hills,  General  Ian  Hamilton 
states  in  his  "Staff  Officer's  Scrap  Book"  :     'T  am  be- 


25 

coming  increasingly  certain,  as  I  gain  in  experience,  that 
the  defense  Hnes  of  the  forbidding,  precipitous  type  are 
in  truth  generally  more  open  to  attack  than  a  simple, 
gently  rising  terrain,  which  furnishes  those  who  hold  it 
with  a  wide,  smooth  field  of  fire  and  good  positions  for 
their  guns." 

19.  Location  of  Works  in  the  Second  Line. — The 
same  general  principles  apply  to  the  selection  of  the  sites 
for  works  or  supporting  points  in  the  second  or  retired 
line.  It  should  be  possible  to  bring  from  it  a  concen- 
trated and  heavy  fire  on  any  part  of  the  outer  line  which 
has  been  captured,  and  to  confront  the  assailants  with 
a  fresh  series  of  works  which  must  be  carried  before 
they  can  reach  the  object  of  their  efforts. 

20.  Good  means  of  communication  between  all  parts 
of  the  general  line  of  defense,  and  also  from  the  town 
or  headquarters  to  all  points  on  the  line,  are  of  vital 
importance. 

The  facility  with  which  artillery  and  the  reserves 
will  be  able  to  move  in  every  direction  in  rear  of  the 
line  of  battle  constitutes  an  element  of  enormous  weight 
which  must  be  prepared  for  with  the  greatest  care,  and 
which  may  demand  the  opening  of  passages  through 
woods,  the  construction  of  small  bridges  across  streams, 
etc.      (See  paragraphs  13  and  75.) 

21.  Lines  of  Retreat. — Since  is  is  necessary  to  fore- 
see everything,  the  commander  will  look  into  the  eventual- 
ity of  a  retreat,  and  will  cause  to  be  made  all  the  necessary 
preparations  to  insure,  if  necessary,  its  good  execution 
and  to  prevent  the  enemy  from  changing  it  into  a  rout. 
The  preparation  for  the  retreat  will  comprise  the  works 
of   communication   and   the    organization   of   points   of 


26 

support  for  the  retreat.  These  last  will  consist  of  posi- 
tions of  limited  extent  barring  the  roads  and  covering 
especially  certain  points  that  must  be  passed,  such  as 
bridges  or  various  other  positions  at  which  a  small  force 
could  stop  the  enemy  quite  a  long  time  and  make  him  lose 
contact  with  the  main  body  of  the  forces,  and  insure  the 
safe  passage  of  the  latter.  These  points  of  support 
should  be  echeloned  in  depth  and  the  artillery  will  play 
the  principal  role  in  their  defense. 


27 


CHAPTER  II. 
Tactical  Organization  of  Infantry  in  Defense. 

22.  Division  into  Sections. — A  large  fortress  or  de- 
fensive position  would  be  far  too  extensive  for  all  the 
troops  to  be  directly  supervised  by  one  man.  It  should 
therefore  be  sub-divided  for  purposes  of  command  into 
several  sections,  each  under  the  command  of  an  officer 
with  a  suitable  staff. 

Each  section  should  be  completely  independent,  both 
tactically  and  as  regards  administration;  subject,  of 
course,  to  the  general  control  of  the  fortress  commander. 

23.  Strength  of  the  First  Line,  Supports  and  Re- 
serves.— Every  fortified  post  in  the  front  line  of  the 
section  would  be  occupied  by  its  own  infantry  garrison. 
In  rear  of  the  works,  if  possible  close  to  them  and  never 
over  300  yards  distant  from  them,  and  under  good  cover, 
will  be  the  supports,  whose  strength  would  vary  accord- 
ing to  the  necessities  of  the  case,  but  would  generally 
be  from  one-half  to  two-thirds  of  that  of  the  garrison 
of  the  post.  Then  in  rear  again  and  at  a  central  position 
as  regards  the  whole  section,  would  be  the  local  or  "sec- 
tion" reserve.  Its  strength  would  depend  upon  the 
defensive  strength  of  the  works  along  the  front  of  the 
section.  If  the  latter  were  strong  and  the  means  of 
communication  to  them  were  good  and  not  long,  the 
number  of  troops  in  the  works,  including  their  imme- 
diate supports,  could  be  kept  low,  and  the  number  in 
reserve  increased.  The  advantage  of  this  would  be  that 
it  would  relieve  as  large  a  number  of  troops  as  possible 


28 

from  an  exhausting  and  demoralizing  life  in  the  advance 
works  under  constant  shell  fire.  If,  however,  the  nature 
of  the  ground  made  the  outer  defensive  position  a  weak 
one,  or  if  the  reinforcements  could  not  reach  them  with- 
out long  delays,  then  a  considerable  number  of  troops 
must  be  kept  well  up  to  the  front,  and  the  reserve  would 
be  proportionately  less. 

The  artillery  belonging  to  the  section  would  usually 
remain  either  in  emplacements  in  the  front  line  or  under 
cover  close  in  rear.  There  might,  however,  be  some  light 
pieces  with  the  section  reserve  troops. 

The  works  will  most  frequently  be  combined,  for  the 
purpose  of  command,  into  groups  which  one  battalion  can 
defend,  one  portion  of  its  defenders  forming  the  garrison 
for  the  trenches  and  the  other  part  a  movable  force  in 
support,  intended  either  to  reinforce  the  line  of  fire  or 
to  be  used  in  counter  attack.  Dependent  upon  circum- 
stances, the  battalion  will  ordinarily  have  either  two  com- 
panies in  garrison  in  the  trenches  and  two  in  support,  or 
three  companies  in  the  trenches  and  one  in  support.  This 
last  subdivision  is  suitable  for  a  point  of  support  which 
is  expected  to  offer  only  a  weak  resistance,  or  to  parts 
of  the  field  of  battle  which  are  approachable  by  the 
adversary  with  difficulty  and  are  provided  with  good 
flank  protection;  the  parts  easily  approachable  and  from 
which  a  vigorous  resistance  must  be  demanded,  on  the 
contrary,  will  have  a  larger  movable  force. 

Taking  into  consideration  the  fact  that  the  assailant 
will  always  try  to  bombard  effectively  with  his  artillery 
the  works  to  be  attacked  and  the  approaches  thereto,  and 
that  in  consequence  the  movement  from  the  rear  to  the 
front  will  be  very  difficult  to  execute  without  considerable 
losses,  unless  good  covered  approaches  exist,  the  com- 


29 

panics  of  the  garrison  mnst  have  all  of  their  numbers 
in  the  trenches,  even  thou^^h  they  wish  at  certain  times 
to  engage  only  a  part  of  their  forces  and  to  keep  a  part 
for  reinforcements.  It  seems,  moreover,  that  the  con- 
dition of  never  permitting  the  enemy  to  have  the  superi- 
ority of  fire  demands  that,  at  a  given  moment,  it  should 
be  possible  to  place  the  whole  company  in  line  imme- 
diately; and  this  will  be  most  easily  secured  in  the 
described  manner. 

24.  The  position  of  the  section  reserve  would  form 
the  headquarters  of  the  section,  and  should  be  out  of 
sight  of  the  enemy.  It  should  also  be  on  or  near  a  main 
radial  road  of  communication,  and  from  the  camp  a  road 
or  roads  should  lead  to  different  parts  of  the  front  line. 
It  should  be  connected  by  telephone  with  each  of  the 
fortified  positions  in  the  defensive  line,  with  headquarters 
and  the  main  depots. 

25.  The  points  of  support  of  the  second  line,  like 
those  of  the  first,  ought  always  to  have  their  fixed  garri- 
son without  counting  upon  the  movable  troops ;  this  is 
the  only  means  of  being  certain  that  the  works  will  be 
occupied  at  the  proper  moment.  In  case  of  taking  up 
the  offensive  again,  they  will  have  to  be  abandoned,  and 
the  units  charged  with  their  defense  will  then  constitute 
the  reserve. 

26.  General  Reserve. — In  addition  to  the  section  re- 
serves there  should  be  in  all  cases  a  general  reserve  for 
the  whole  position.  It  should  be  encamped  in  a  central 
location  and  should  be  of  as  mobile  a  nature  as  is  prac- 
ticable. 

The  disadvantages  of  the  great  extent  of  the  position. 
which  has  to  be  taken  up  for  defense  at  the  present  day, 


30 


is  largely  neutralized  if  a  considerable  portion  of  the 
defenders  are  kept  as  a  mobile  reserve  force,  as  the  for- 
tified positions  may  in  such  case  be  few  in  number  and 
far  apart;  they  should,  however,  always  be  individually 
strong. 


31 


CHAPTER  III. 
Tactical  Employment  of  Artillery  in  Defense. 

27.  The  disposition  of  the  artillery  will  be  different 
from  that  of  the  infantry.  It  will  not  usually  be  desir- 
able to  keep  any  of  the  heavier  guns  or  howitzers  in  the 
center  of  the  defended  area  as  a  general  reserve.  As  a 
general  rule,  it  will  be  required  to  have  all  the  heavy 
artillery  iji  the  front  line  from  the  very  beginning  of  the 
siege,  in  order  to  crush  the  besieger's  guns,  and  prevent 
his  building  batteries,  so  that  only  the  shorter  ranging 
pieces  sTiouId^lbe  kept  in  rear.  If,  Jiowever,  the  defense 
is  very  weak  in  artillery,  the  guns  might  have  to  be  kept 
under  cover  so  as  to  have  them  available  for  use  in  the 
later  and  more  critical  phases,  particularly  in  the  event 
of  an  assault. 

28.  Mobility. — All  the  guns  should  be  movable  and 
ther^shauld  be  a  large  number  of  alternate  emplacements, 
and  good  and  direct  communications  hidden  from  the 
enemy 's'^viewT'  Mobility,  in  fact,  is  the  chief  factor. 

29.  Armament. — Generally  speaking,  the  armament 
of  a  first-class  fortress  would  consist  mainly  of  howitzers 
and  mortars  from  5-inch  caliber  upwards.  It  would  also 
have  a  certain  number  of  long  range  heavy  guns,  such 
as  the  6-inch  ;  also  a  proportion  of  less  powerful  pieces, 
which  should  be  of  the  rapid-fire  class,  the  4.7-inch  and 
long  12-pounder  being  the  most  useful  sizes.  Long  range 
direct-fire  guns  are  required  to  keep  the  attackers  at  a 
distance  and  to  act  upon  them  if  they  attempt  to  come 
out  into  the  open;  howitzers  and  mortars  are  required  to 


32 

search  out  their  trenches,  drop  heavy  shells  into  their 
gun  emplacements,  break  down  overhead  cover,  and 
search  hollow  ground,  reverse  slopes  of  hills,  ravines,  and 
other  places  where  they  might  find  cover.  Howitzers  and 
mortars  are  ineffective  at  ranges  under  1,000  yards,  so 
that  for  this  stage  of  the  attack,  guns  only  can  be  relied 
on.  Shrapnel  fire  from  guns  is  also  recjuired  against 
attackers  in  the  open. 

The  proportion  of  the  guns  to  the  howitzers  and  mor- 
tars will  depend  to  a  certain  extent  on  the  topography. 
If  the  ground  in  front  is  broken,  affording  abundant 
cover,  and  precluding  long  range  fire,  then  howitzers  and 
mortars  should  predominate.  Where  the  foreground  is" 
open  for  a  long  distance,  or  the  defensive  position  very 
commanding,  the  proportion  of  guns  might  be  greater. 

30.  The  location  of  the  emplacements  for  the  heavy 
artillery  will  depend  mainly  upon  the  duty  that  each  piece 
has  to  perform.  Generally  this  duty  is  to  operate  against 
an  enemy  who  is  attacking  the  main  supporting  points. 
By  this  is  meant  that  the  defense  of  these  points,  rather 
than  that  of  the  intervals  between  them,  is  the  object 
chiefly  to  be  aimed  at,  for  an  attack  through  the  intervals 
need  not,  as  a  rule,  be  feared.  At  the  same  time,  means  of 
bringing  a  cross  fire  over  the  intervals  are  not  to  be 
neglected.  Certain  also  of  the  pieces,  generally  howitzers 
and  mortars,  will  have  specified  duties  to  perform,  such 
as  to  enfilade  reverse  slopes  of  hills,  hollow  ground  or 
ravines,  which  are  screened  from  frontal  fire;  and  in  gen- 
eral, the  artillery  positions  will  be  so  placed  as  to  bring 
a  heavy  fire  over  all  the  ground  to  be  traversed  by  the 
assailants. 

31.  The  dispersion  of  the  guns  in  an  artillery  posi- 
tion has  several  advantages.     It  renders  it  difficult  for 


33 

the  attackers  to  concentrate  their  fire;  it  brings  a  con- 
verging fire  from  a  wide  arc  to  bear  on  the  object  specified 
for  attack;  it  permits  of  far  greater  latitude  in  the  selec- 
tion of  sites  for  emplacements  and  in  taking  advantage 
of  the  ground  to  obtain  concealment,  and  it  very  con- 
siderably does  away  with  the  demoralizing  effect  pro- 
duced by  a  heavy  shell  fire  in  a  comparatively  small  area. 
The  guns  should  therefore  be  dispersed,  but  their  fire 
must  be  capable  of  concentration  by  complete  telephonic 
communication  between  the  guns,  observing  stations  and 
commanders. 

32.  Position  zvith  Reference  to  the  Infantry. — If  the 
existence  of  high  ground  in  rear  admits  of  it,  the  defend- 
ing artillery  may  fire  over  its  own  infantry  positions, 
or  the  artillery  itself  may  be  in  two  tiers,  the  direct  firing 
guns  being  in  advance,  and  the  howitzers,  firing  over 
them  from  retired  positions.  It  may  be  necessary  for 
some  of  the  guns — for  instance,  those  entrusted  with  the 
duty  of  enfilading  hidden  ground  in  front  of  the  main 
position — to  be  placed  well  to  the  flank  of  the  infantry 
positions ;  that  is  to  say,  practically  in  the  intervals  be- 
tween the  supporting  points.  In  all  such  cases  they 
require  to  be  defended  by  infantry,  for  whom  intrenched 
positions  should  be  nrovided  near  them.  (See  paragraph 
15.) 

It  is  not  necessary  that  any  of  the  guns  may  be  able 
to  defend  their  fronts  by  their  own  fire,  as  this 
duty  can  be  more  conveniently  and  effectively  carried 
out  by  infantry. 

33.  Location  of  Guns. — A  somewhat  commanding 
position  is  an  advantage  for  guns  particularly  for  pur- 
poses of  observation.  If  the  sites  are  on  a  hill  they  are, 
for  purposes  of  concealment,  best  placed  a^little  way  down 


34 

from  the  crest ;  at  all  events  not  on  the  sky  line,  pro- 
vided means  of  access  are  obtainable  from  the  rear.  It 
may  sometimes,  however,  be  better  to  put  them  in  posi- 
tions somewhat  drawn  back  from  the  crest  of  the  hill. 
Here  they  will  be  less  easy  to  hit.  and  the  guns  can  be 
more  easily  withdrawn  or  brought  up.  It  is  possible  that 
from  such  a  position  a  good  deal  of  ground  at  the  foot 
of  the  hill  could  not  be  seen,  but  this  could  generally  be 
dealt  with  by  pieces  from  another  part  of  the  position. 

34.  Location  of  Hoivitsers  and  Mortars. —  Howit 
zers  and  mortars,  which  can  fire  over  an  intervening  ob- 
stacle, provided  its  height  is  not  such  as  to  intercept  the 
projectile  in  its  flight,  and  whose  fire  can  be  controlled 
from  observing  stations  can,  and  would  usually,  be  placed 
in  retired  situations  on  the  reverse  slope  of  hills,  etc. 
Here  they  would  be  entirely  unseen,  and  could  hardly 
be  hit.  Good  sites  for  observing  stations  would  in  such 
a  case  be  of  the  first  necessity,  and  these  must  obviously 
be  as  inconspicuous  as  possible. 

35.  Indirect  Fire  for  Guns. — The  heavy  direct  firing 
guns  could  also  be  fired  in  the  same  manner,  if  it  were 
considered  desirable  to  put  them  in  retired  positions ;  but 
with  low  trajectory  weapons  such  positions  would  be  less 
easy  to  find,  and  such  an  arrangement  would  be  almost 
certain  to  result  in  a  considerable  portion  of  the  ground 
at  medium  and  short  ranges  being  screened  from  the 
guns;  moreover  it  is  undesirable  to  rely  entirely  on  ob- 
5er^'ing  stations  which  may  be  wrecked,  so  it  is  better 
that  nearly  all  the  direct  firing  guns  should  be  capable 
of  being  laid  direct  on  their  objects.  (See  paragraph 
68.) 


35 

36.  Rapid-Fire  Guns. — In  addition  to  the  heavier 
types  of  guns,  it  is  very  desirable  to  have  for  use  in  the 
later  stages  of  the  siege  a  number  of  light  guns  of  the 
rapid-fire  class,  such  as  6-pounder  and  3-pounder  rapid- 
fire  and  the  1-pounder  automatic  or  pom-pom.  Guns  of 
this  class  are  of  course  useless  against  earthworks,  but 
they  fulfil  most  useful  functions  during  the  later  stages 
of  a  siege.  For  instance,  in  the  event  of  an  assault  they 
will  assist  in  bringing  an  overwhelming  fire  to  bear,  and 
at  any  time  should  the  besieger  offer,  even  for  a  few 
moments,  a  target  in  the  open,  their  rapidity  of  working 
will  permit  of  the  opportunity  being  availed  of. 

For  such  guns  there  should  be  a  number  of  alternate 
and  well-concealed  positions;  the  principle  of  their 
employment  should  be  surprise,  combination,  and  the 
taking  advantage  of  every  opportunity. 

37.  Field  Guns. — A  mimber  of  3-inch  field  guns 
could  also  be  most  usefully  employed  in  the  defense  of  a 
fortress.  They  need  not  be  assigned  to  any  particular 
positions,  but  might  be  kept  with  the  reserve  troops  and 
pushed  up  into  any  part  of  the  front  line  when  they  are 
required. 

38.  Machine  guns  will  fulfil  a  most  useful  purpose 
in  a  fortified  position.  They  can  be  kept  concealed  when 
not  in  use,  and  even  when  in  the  act  of  firing,  afford 
so  small  a  target  as  to  be  hardly  visible.  A  few  such 
weapons  in  an  intrenched  position  permit  of  the  greater 
part  of  the  garrison  being  kept  well  under  cover;  for  in 
the  event  of  an  assault,  they  enable  a  heavy  fire  to  be 
developed  by  their  attendants.  In  the  defense  of  a  flank, 
in  a  position  where  a  line  of  infantry  would  be  visible 
and  liable  to  enfilade  fire,  a  single  machine  gun  judiciously 


36 

posted  behind  a  bush  or  rock  or  in  a  small  pit  could 
entirely  escape  observation.  To  cover  particular  points 
such  as  a  bridge  or  ford,  they  are  also  most  valuable. 
Every  fortress,  therefore,  should  be  equipped  with  a 
good  number  of  these  useful  v^^eapons.  Each  infantry 
v;rork  should  have  some  assigned  to  it,  and  there  should 
also  be  a  number  in  reserve. 


37 


CHAPTER  IV. 
Design  of  Infantry  Works. 

39.  It  is  undesirable  to  indicate  more  than  the  gen- 
eral principles  of  the  design  of  the  works.  In  order  to 
make  these  clear  it  is  necessary  to  give  some  designs,  with 
the  understanding  that  they  are  not  at  all  rigid,  and 
sliould  be  modified  to  suit  the  ground. 

40.  There  are  four  general  objects  to  be  aimed  at 
in  preparing  a  given  area  for  defense : 

1.  It  should  have  the  utmost  development  of  fire  to 
the  front,  and  to  a  somewhat  less  degree  to  the  flanks. 

2.  The  works  should  be  so  arranged  that  they  will 
offer  as  shallow  a  target  to  the  enemy  as  possible. 

3.  They  should  be  made  inconspicuous  and  difficult 
to  distinguish. 

4.  They  should  afford  rapid  and  covered  communi- 
cation from  each  work  or  part  of  the  defensive  line  to 
the  rear,  so  that  supports  may  be  brought  up  with  the 
utmost  rapidity, 

41.  General  Character  of  the  Supporting  Points. — 
Along  certain  parts  of  the  defensible  ground,  where  a 
good  field  of  fire  in  the  required  direction  can  be  obtained, 
will  be  constructed  lines  of  infantry  parapet  with  cover 
in  rear,  connected  by  covered  ways,  perhaps  with  each 
other  and  certainly  with  the  rear.  On  suitable  positions 
for  artillery  fire  will  be  constructed  the  emplacements  for 
the  guns,  also  with  communications  to  the  rear.  The 
selection  of  both  these  infantry  and  gun  positions  will  be 
governed  by  the  four  main  principles  stated  above. 


38 

To  permit  of  full  scope  for  the  defender's  rifle  fire, 
all  that  is  needed  is  a  simple  parapet  to  fire  over.  In 
trace  this  should  follow  the  contour  of  the  ground,  and 
should  therefore  seldom  be  straight,  and  never  on  any 
geometrical  plan.     (See  paragraph  13.) 

It  is  necessary,  in  order  to  cover  the  field  of  fire  com- 
pletely, that  the  works  be  traced  along  the  military  crest 
itself  or  simply  on  the  gently  sloping  ground  following 
approximately  the  contours  of  the  ground. 

This  disposition  presents  one  great  advantage ;  which 
is,  that  it  does  not  ofl^er  to  the  eye  of  the  enemy's  observer 
any  geometrical  form  betraying  the  work  of  man.  No 
other  plan  will  answer;  the  crest  of  fire,  lending  itself  to 
all  the  changes  of  the  ground,  cannot  be  perceived,  even 
at  short  ranges.  Moreover,  neither  the  trace  nor  the 
execution  will  be  complicated. 

42.  Redouts  cannot  generally  be  used  in  situations 
exposed  to  artillery  fire  unless  they  can  be  so  arranged 
that  they  cannot  be  recognized  as  such  from  the  enemy's 
artillery  positions.  A  favorable  site  is  one  which  com- 
mands the  ground  around  it  to  effective  rifle  range  and 
is  not  visible  from  artillery  ranges. 

In  preparing  a  defensive  position,  if  sites  meeting  the 
foregoing  conditions  can  be  found  on  which  redouts  can 
be  built  to  flank  the  adjacent  trenches,  they  should  by 
all  means  be  built.  Redouts  in  good  position  in  rear 
of  a  line  form  valuable  supporting  points. 

The  Fort  Riley  redout  (Fig.  205,  E.  F.  M.)  and  the 
Russian  and  Japanese  redouts  (Figs.  1  and  2)  are  excel- 
lent types  of  a  modern  redout.     (See  paragraphs  102-4.) 

In  speaking  of  the  Shanlantzu  redout.  Major  Kuhn 
states :  "In  my  judgment,  it  has  the  best  profile  and  trace 
of  any  seen  during  the  war,  affording  good  cover,  small 


39 

artillery  target,  and  strong  frontal  fire  for  infantry.  The 
Japanese  constructed  a  somewhat  similar  redout  near 
Kangpienhsien  and  it  is  surmised  that  the  Shanlantzu 
redout  served  as  a  model. 

''The  polygonal  trace  with  a  broad  front  and  shallow 
depth  appears  to  best  meet  the  requirements  for  a  closed 
work  under  modern  conditions,  affording  a  strong  frontal 
fire  and  a  minimum  target  to  the  artillery.  While  the 
reduction  in  depth  of  closed  works  imposed  by  the  search- 
ing i)()\ver  of  artillery  reduces  the  volume  of  flank  fire  and 
diminishes  the  value  of  such  works  in  an  extensive  forti- 
fied line  in  fiat  country,  forts  and  redouts  have  not  lost  all 
their  importance  and  are  still  needed  to  afford  points  of 
support  to  a  defensive  line.  The  employment  of  machine 
guns,  moreover,  enables  small  works  with  short  flanks 
to  deliver  a  volume  of  fire  which  makes  the  size  of 
works  and  their  garrison  a  matter  of  minor  importance. 

"It  is  to  be  noted  that  none  of  the  forts  or  redouts 
provide  for  the  emplacement  of  artillery  in  their  interiors. 
The  artillery  was  placed  either  in  the  line  of  the  trenches 
connecting  the  forts  and  redouts,  or,  more  generally,  in 
a  retired  position  several  hundred  yards  in  rear  of  the 
front  line. 

'Tt  is  only  in  perfectly  flat  and  unbroken  country  that 
redouts  need  approximate  the  type  forms  of  closed  works 
shown  in  text  books.  In  ordinary  diversified  topography 
many  points  will  be  found  which,  with  simple  trenches, 
cover  for  men  and  ammunition  and  good  approaches,  will 
fulfil  the  requirements  of  redouts  without  the  use  of 
closed  works." 


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43 

43.  An  introicJuncnt  is  a  shield ;  its  object  is  to  make 
the  defender  safe,  either  when  at  rest  or  when  in  the 
firing-  position,  against  the  action  of  the  enemy's  pro- 
jectiles ;  its  profile  is  therefore  dependent  upon  the  arma- 
ment in  use.  It  must  necessarily  vary  with  that  and 
undergo  a  parallel  evolution. 

The  profile  depends  furthermore,  especially  for  in- 
trenchments  made  on  the  field  of  battle,  upon  the  time 
that  the  defender  can  give  to  their  execution.  This  time 
Vv-il!  always  be  short,  first,  on  account  of  the  fatigue  that 
can  be  imposed  upon  the  troops  and  which  must  be  re- 
duced to  a  minimum;  and  second,  because  it  will  not 
usually  be  possible  to  determine  exactly,  very  long  in 
advance,  the  ground  of  the  struggle. 

44.  Effect  of  Wcopons. — The  rifle  and  machine  gun 
shoot  a  bullet  whose  ])enetrati()n  in  earth  varies  according 
to  the  arm.  the  distance  and  the  nature  of  the  soil,  from 
24  to  40  inches.  This  last  penetration  hardly  applies 
except  to  clay  at  very  short  ranges.  Thirty-two  inches 
can  be  considered  as  the  normal  maximum. 

Shrapnel  from  field  guns  fired  with  a  time  fuse  has 
no  effect  upon  intrenchments  which  have  a  sufficient 
thickness  to  resist  a  rifle  bullet.  Tt  can  only  have  effect 
upon  the  defenders  when  the  latter  arc  firing.  Tt  is 
powerless  when  the  men  are  resting  behind  the  parapet, 
either  seated  or  lying  down  with  their  backs  to  tlie  mass 
or  protected  by  it  under  the  sh^pe  of  about  1  on  4. 

The  same  shell  fired  with  a  percussion  fuse  pene- 
trates rather  deeply  into  the  earth  of  a  recently  con- 
structed parapet  when  the  projectile  falls  upon  the 
exterior  slope.  Upon  bursting  it  may  form  craters  as 
large  as  60  inches  in  diameter  and  20  inches  in  depth. 
But  when  the  projectile  falls  upon  the  suj^erior  slope,  it 


44 

cuts  out  a  furrow  of  not  more  than  6  to  8  inches  in 
depth  at  the  most,  and  carries  away  but  httle  earth.  In 
other  words,  it  ricochets.  Such  shells  fired  against  men 
placed  upon  the  banquette  of  an  intrenchment  produce 
but  little  effect.  At  2,000  yards  it  can  hardly  be  hoped 
to  get  more  than  one  man  wounded  for  every  shell,  even 
with  a  perfectly  regulated  fire.  If  the  men  are  seated  or 
lying  down  with  their  backs  to  the  parapet,  the  result  is 
practically  nothing. 

In  general,  high  explosive  shells  from  field  guns  pro- 
duce no  effect  upon  the  unprotected  personnel  unless 
they  burst  very  close  to  the  object.  They  therefore  re- 
quire very  great  accuracy  of  fire.  Fired  against  earthen 
parapets  in  which  they  can  enter,  these  shells  give  quite 
a  considerable  effect,  but  the  complete  destruction  of  this 
class  of  works  can  only  be  obtained  by  a  prolonged  fire, 
regulated  with  accuracy,  which  will  always  necessitate  a 
relatively  great  expenditure  of  ammunition.  The  per- 
sonnel sheltered  behind  these  parapets  will  suffer  but  lit- 
tle. Those  shots  alone  which  burst  at  the  crest  will  pro- 
duce serious  effects.  But  these  shots  must  be  considered 
as  altogether  accidental,  however  well  regulated  the  fire 
may  be. 

Shrapnel  from  siege  guns  fired  with  a  time  fuse  has 
great  efficiency  against  troops  without  cover  up  to  a  range 
of  7,ooo  yards  for  guns  and  5,000  yards  for  howitzers. 
But  as  soon  as  the  personnel  is  materially  sheltered  the 
effect  of  these  shells  becomes  ver}^  small,  even  with  plung- 
ing fire,  and  can  be  completely  nullified  if  the  defenders 
protect  themselves  by  light  roofs  such  as  hurdles  covered 
with  from  4  to  6  inches  of  earth,  or  by  means  of  thick 
planks.  Under  these  conditions  the  greater  number  of 
balls  and  pieces  of  shells  are  stopped.     Fired  with  per- 


45 

cussion  fuses  against  obstacles  and  accessory  defenses, 
shrapnel  has  an  effect  very  inferior  to  that  of  high  ex- 
plosive shells  of  the  same  caliber. 

Like  projectiles  of  small  caliber,  those  of  large  caliber 
ricochet  when  they  are  fired  so  that  the  angle  of  fall  is 
less  than  17°.  The  ricochet  can  also  be  produced  when 
the  angle  of  fall  varies  between  17°  and  30°,  depending 
upon  the  initial  velocity  and  the  nature  of  the  soil.  When 
the  shell  ricochets,  it  explodes  in  the  air,  and  then  pro- 
duces very  small  and  altogether  uncertain  results. 

When  shells  of  large  caliber  are  employed  against  a 
parapet,  the  shots  which  strike  the  crest  are  very  effica- 
cious against  the  troops  sheltered  behind  it,  but,  as  with 
projectiles  of  small  caliber,  these  shots  will  always  be 
altogether  accidental,  even  with  a  very  well  regulated 
fire. 

Practically  all  of  the  above  effects  were  obtained  in 
the  test  of  the  field  redout  at  Fort  Riley  in  1907  (fig.  205, 
E.F.M.),  where  high  explosive  shells  from  field  and 
siege  guns,  and  siege  howitzers  were  fired  at  the  work; 
which  has  a  triangular  profile  and  low  command.  Prac- 
tically the  only  shells  which  penetrated  the  parapet  and 
splinter-proofs  were  those  of  the  7-inch  siege  howitzer. 
(See  Major  Kuhn's  comments,  par.  46.) 

45.  Profiles. — From  the  above  discussion  on  the 
effect  of  projectiles,  the  conditions  which  a  good  profile 
must  satisfy  are  apparent. 

The  exterior  slope  of  the  parapet  should  have  an  in- 
clination of  not  less  than  1  on  5.  This  corresponds  to 
an  angle  of  about  11°,  and  the  mean  value  of  the  angle 
of  fall  of  projectiles  from  the  present  field  guns  is  taken 
as  6°.  With  this  slope,  projectiles  fired  with  a  service 
charge  from  a  field  gun  will  nearly  always  ricochet.     This 


46 

gives  the  personnel  almost  complete  protection  from  field 
guns  fired  with  percussion  fuses. 

To  make  a  parapet  proof  against  rifle  and  macliine 
gun  bullets  and  shrapnel  balls,  a  thickness  of  32  to  40 
inches  is  sufficient.  Thus  behind  a  para])et  32  inches 
thick  with  an  exterior  slope  of  1  on  5,  the  defender  is 
practically  altogether  sheltered  from  rifle  and  machine 
gun  fire  and  from  projectiles  fired  with  a  service  charge 
from  long  range  pieces.  Certain  accidental  shots  on  the 
crest  alone  can  injure  him. 

It  is  apparent  that  the  profiles  gi\-en  in  the  manuals 
do  not  satisfy  the  above  conditions  in  regard  to  the  ex- 
terior slope.  This  is  usually  the  natural  slope  of  loose 
soil,  or  about  1  on  1.  Every  shell  striking  the  exterior 
slope  will  penetrate  the  mass  of  the  parapet  and  produce 
therein  considerable  effect.  These  profiles  therefore 
ought  to  be  modified  in  this  regard  and  ought  also  be 
modified  in  other  respects. 

Having  determined  the  means  of  sheltering  the 
defender  from  the  projectile  with  a  flat  trajectory,  the 
next  consideration  is  to  afford  protection  from  high  angle 
fire.  This  fire  will  be  executed  most  frequently  against 
the  intrenchments  by  means  of  high  explosive  shells,  and 
their  powerful  effects  are  well  known.  But,  in  order  that 
these  effects  may  be  produced,  it  is  necessary  to  hit  the 
trenches,  that  is  to  say,  the  fire  must  be  perfectly  regu- 
lated. It  is  manifestly  impracticable  to  try  to  shelter  the 
men  under  great  masses  of  earth  in  intrenchments  on  the 
field  of  battle.  It  can  no  longer  be  attempted  even  in  the 
intrenchments  constructed  in  a  line  of  investment ;  and, 
as  a  general  thing,  endeavors  should  only  be  made  to 
render  the  adjustment  of  the  enemy's  fire  as  difficult  as 
possible. 


47 

In  consequence,  the  relief  of  the  parapet  should  be  re- 
duced as  much  as  circumstances  will  permit,  and  every 
means  possible  should  be  employed  to  render  the  in- 
trenchments  invisible  at  a  distance  (see  paragra[)h  63). 

In  order  to  reduce  the  chances  of  shrapnel  or  shell 
fragments  entering  the  trench,  it  should  be  as  narrow  as 
practicable.  The  earth  for  the  parapet  can  be  obtained 
b}'- deepening  the  trench.  It  ma}'  be  necessary  to  sit 
close  to  the  parapet  in  order  to  avoid  the  projectiles,  and 
the  parapet  will  afford  protection  in  proportion  to  the 
steepness  of  its  interior  slope.  It  should  be  vertical  if 
the  earth  will  stand  at  that  angle.  Most  soils  will  stand 
a  short  time  in  Aertical  cut,  and  if  there  is  time  for  the 
earth  to  break  due  to  weathering,  there  should  be  time 
to  revet  it  at  the  desired  slope. 

A  good  intrenchment  must  therefore  satisfy  the  fol- 
lowing conditions  in  regard  to  its  profile : 

A  relief  as  small  as  circumstances  will  permit;  a  para- 
])et  limited  on  the  outside  by  a  single  gentle  slope  of 
about  1  on  6;  a  narrow  trench,  interior  and  reverse  slopes 
as  steep  as  practicable,  replaced  even,  if  possible,  by 
vertical  faces.  It  will  be  noticed  that  the  thickness  of 
the  parapet,  which  had  to  be  thought  about  when  the  ex- 
terior slope  was  steep,  no  longer  comes  into  consideration 
when  the  latter  is  replaced  by  the  prolongation  of  the 
superior  slope.  Furthermore,  it  is  not  even  necessary  to 
begin  the  exterior  slope  of  1  on  6  at  the  crest  unless  in 
exceptional  cases  when  an  increased  relief  to  the  parapet 
is  necessary.  Quite  frequently  it  can  be  made  witli  a  flat 
surface  practically  parallel  to  the  ground  from  32  to  40 
inches  in  thickness.  This  will  protect  a  little  more  against 
rifle  bullets,  and  will  not  create  any  sensible  dead  angle 
in  front.     It  w^ill  also  be  more  convenient   for  the  de- 


48 

fender,  who  can  more  easily  support  his  rifle.  In  order 
not  to  have  a  difference  in  lighting  between  this  plat- 
form and  the  slope  of  1  on  6,  which  might  be  seen  at 
times,  it  ought  always  to  be  connected  with  the  exterior 
slope  by  a  curved  surface. 

Profiles  which  satisfy  the  above  conditions  are  shown 
in  figs.  3-8 ;  the  trench  walls  are  all  shown  vertical  as  ex- 
plained above.  For  the  time  necessary  to  construct  these 
profiles  see  Chapter  X. 

Fig.  3  shows  a  profile  which  may  be  used  when  the 
time  available  for  intrenching  is  very  limited ;  it  is  too 
narrow  for  good  communication,  and  for  the  comfort 
of  the  men  occupying  it.  Fig.  4  shows  the  same  profile 
widened  to  3  feet,  which  is  the  minimum  width  ordin- 
arily allowed,  affording  fair  communication,  and  allow- 
ing the  men  to  sit  with  their  backs  to  the  parapet.  The 
command  in  both  these  profiles  is  1.5  feet,  which  is  usu- 
ally the  minimum  that  will  allow  all  the  foreground  to  be 
covered.  (See  par.  105.) 

Figs.  5  and  6  are  triangular  profiles  with  2.5  and  4 
feet  command  respectively ;  in  each  the  trench  is  deepened 
in  the  rear  to  afford  covered  communication.  In  fig.  6  a 
ditch  is  used  to  avoid  excessive  horizontal  movement  of 
the  excavated  earth.  These  profiles  show  the  great  in- 
crease in  labor  necessary  to  secure  increased  command 
and  at  the  same  time  avoid  making  the  parapet  conspicu- 
ous. (See  par.  106.) 

Figs.  7  and  8  show  profiles  of  Japanese  trenches  in 
Manchuria.  In  both  these,  the  earth  not  necessary  for 
the  parapet  was  thrown  to  the  rear.  (See  par.  107.) 

Major  Reichmann  states :  "The  Russian  troops  were 
invariably   intrenched   and    their   trenches   were    heavily 


49 

manned ;  as  many  men  were  generally  put  in  the  trenches 
as  they  would  hold. 

"Wherever  practicable  the  standing  trench  was  em- 
ployed as  being  the  best  protection  against  shrapnel  fire. 
The  kneeling  trench  was  not  employed  unless  lack  of 
time  or  the  character  of  the  ground  made  the  standing 
trench  impracticable.  The  lying-down  trench  I  never 
saw.     *     ^     ^ 

"Tlie  character  of  the  shrapnel  is  such  that  the  lying- 
down  trench  pro\-ides  cover  against  it  only,  but  not 
shelter.  The  man  who  lies  down  converts  his  vertical 
target  into  a  horizontal  one,  but  does  not  diminish  it. 
and  if  his  presence  is  known  or  suspected  by  the  oppon- 
ent's artillery  he  will  not  derive  much  advantage  from  the 
lying-down  trench.  So  far  as  I  can  see.  the  usefulness 
of  this  trench  is  limited  to  the  infantry  on  the  offensive, 
which  has  been  checked  and  must  hold  out  under  the 
enemy's  fire.  Cases  of  this  kind  are  most  likely  to  occur 
in  the  infantry  attack  in  battle. 

"According  to  the  theory  of  battle  the  attacker  should 
in  the  first  place  silence  the  opponent's  artillery.  He  then 
covers  the  defenders'  trenches  with  fire,  and  thus  enables 
his  own  infantry  to  advance  without  undue  loss  to  the 
position  whence  the  final  assault  is  to  be  launched.  In 
order  to  be  able  to  withstand  this  artiller}-  fire  and  enable 
his  infantry  to  rejuilse  the  attacker's  infantrv,  the  gen- 
eral on  the  defensive  must  provide  effective  shelter  for 
his  men.  The  effect  of  shrapnel  fire  is  so  searching,  so 
murderous,  that  this  precaution  is  imperati\'e." 

Major  Kuhn  states :  "In  general  the  Japanese  profiles 
were  characterized  by  lower  parapets,  with  flatter  su- 
perior slopes,  and  wider  trenches  than  the  Russian  works, 
a  portion  of  the  excavated  material  being  thrown  to  the 


50 

reverse  side  of  the  trench.  The  form  of  parapet  adopted 
by  the  Japanse  lends  itself  better  to  concealment,  but  the 
width  of  trench  renders  it  more  exposed  to  shrapnel  fire. 
The  greater  width  of  trench  has  for  its  object,  of  course, 
the  securing"  of  lateral  communication. 

''A  feature  of  all  the  more  elaborate  Japanese  trenches 
was  a  small  berm,  about  10  inches  below  the  crest,  de- 
signed as  an  elbow  rest  and  to  give  great  steadiness  to 
the  rifle.  This  feature  impressed  me  as  possessing  con- 
siderable merit. 

"Low,  flat  parapets  lend  themselves  better  lo  conceal- 
ment, while  deep  narrow  trenches  furnish  the  best  cover. 
Whether  one  form  of  profile  is  better  than  another  will 
depend  upon  circumstances.  For  purely  defensive  pur- 
poses the  deep  narrow  trench  is  unquestionably  tlie  best, 
but  where  offensive  movements  are  contemplated  a  more 
open  trench  of  the  Japanese  type  is  preferable,,  not  only 
because  it  affords  good  lateral  communications  and  an 
easier  exit,  but  because  its  more  open  construction  is 
better  suited  to  maintaining  a  proper  temper  in  troops 
which  are  to  assume  the  offensive. 

*Tn  their  lines  north  of  Mukden  near  Chinchiatun  the 
Japanese  introduced  ditches  along  several  portions  of  the 
front.  These  ditches  were  located  20  to  30  feet  in  front 
of  the  fire  trench  and  were  flanked  1:)y  field  caponiers 
located  at  the  salients  or  re-entrants  and  connected  to  the 
fire  trench  by  a  sunken  and  covered  passageway.  The 
ditches  were  about  6  feet  deep,  5  feet  wide  at  the  bottom, 
with  side  slopes  of  2  on  1  and  3  on  1."     (  See  fig.  2.) 

At  Port  Arthur  the  trench  shown  in  profile,  fig.  9, 
was  constructed  700  to  800  yards  in  front  of  the  main 
line.  It  was  not  connected  with  other  trenches,  its  com- 
munication with  the  rear  was  very  difficult,  it  had  very 


^t aridin^  Trer)ches.         ^ 


{-4:t 


Fi^.  9. 


/Russian  rre7?c/7  at  Port    /J r thur 

5  O  5  (O  (6   FEET 

Scale 


JH 


53 

little  support  from  other  sections,  and  yet,  notwithstand- 
ing all  that,  it  managed  to  hold  out  almost  a  month.  Its 
length  was  about  600  yards  and  its  garrison,  one  company 
of  200  men,  or  one  man  per  3  yards.  Each  man  was  pro- 
tected on  the  sides  with  sand  bag  traverses  and  provided 
with  head  cover.  A  small  cave  was  made  in  the  wall  at 
the  bottom  of  the  trench  for  keeping  a  supply  of  cart- 
ridges. The  parapet  was  of  earth  21  feet  high  and  7  feet 
thick  and  well  concealed  with  sod.     (See  par.  108.) 

46.  Some  form  of  head  cover  should"  be  provided, 
otherwise  the  defenders  would  be  absolutely  prevented 
from  manning  the  parapet  for  firing  purposes,  by  a  heavy 
fire  of  musketry  and  shrapnel.  For  different  forms,  see 
E.  F.  M.,  par.  13. 

A  good  loophole  should  not  be  visible;  from  a  dis- 
tance, it  should  blend  into  the  parapet,  which  can  be  se- 
cured by  adding  earth  in  front  and  at  the  sides ;  the  open- 
ing of  the  loophole  should  not  project  on  the  sky  over 
the  outline  of  the  breastwork.  Generally  speaking,  the 
construction  and  masking  of  loopholes  constitutes  a  very 
delicate  work  requiring  great  attention.  The  opening 
should  be  masked. 

A  notched  parapet  is  shown  in  fig.  10,  and  the  pro- 
tection afforded  a  man  firing  is  indicated.  (See  par.  109.) 

In  the  Russo-Japanese  War  at  Port  Arthur,  a  loophole 
cover  (a  light  splinter-proof  over  the  loophole)  was 
found  necessary  to  protect  men  firing,  from  shrapnel. 
This  is  shown  in  fig.  9,  and  an  enlarged  section,  in  fig. 
11.     (See  par.  110.) 

Loopholes  should  not  be  at  intervals  less  than  one 
yard,  to  avoid  weakening  the  parapet. 

When  the  head  cover  is  not  considered  advisable,  a 
substitute  consists  in  providing  sand  bags  stored  in  the 


54 

trenches.  When  the  moment  for  opening"  fire  arrives, 
each  solcher  can  lay  a  sand  bag  npon  the  parapet,  prac- 
tically parallel  to  the  direction  of  his  fire.  This  gives  an 
improvised  head  cover  which  is  movable  and  which  has 
not  served  the  enemy's  artillery  in  discovering  the  work, 
and  now  plays  its  part  in  the  protection  by  almost  com- 
pletely sheltering  the  head  of  the  marksman.  Some  bul- 
lets may  go  through  it  perhaps,  but  it  will  stop  a  great 
number  to  such  an  extent  that  the  vulneral^le  surface  of 
the  man  behind  it  will  be  very  materially  reduced. 

General  Ian  Hamilton  states :  "From  Majuba  time 
onwards  I  have  always  held  the  opinion  that  loopholes 
(IouIdIc  the  value  of  any  cover,  and  all  I  have  seen  since 
has  tended  to  confirm  me  in  this  view.  Even  during  an 
attack  the  soldier  can  usually  find  cover  for  his  body,  and 
if  not,  he  can  rapidly  extemporize  it  with  stones  or  spade 
work.  Under  such  conditions  he  is  at  least  on  an  equal 
footing  with  an  adversary  who  has  to  show  his  head  over 
the  straight  line  of  a  conspicuous  breastwork  before  he 
can  fire.  Indeed  he  is  far  less  visible,  and  thus  less  vul- 
nerable to  distant  artillery  fire.  To  give  a  defender  that 
indisputable  advantage  which  is  necessary  to  counteract 
the  depression  of  having  to  wait  whilst  the  enemy  is  ad- 
vancing, he  should  be  pro\ided  with  a  loophole,  or  head 
cover  of  some  sort.  Then,  and  only  then,  will  the  aver- 
age soldier  retain  confidence  enough  to  use  cool,  deliber- 
ate, aimed  fire  amidst  the  showers  of  shrapnel  and  rifle 
bullets  which  whistle  and  sing  past  his  ears.  Otherwise 
he  fires  hastily  and  fires  high,  the  instinct  of  self-preserva- 
tion impelling  him  to  'loose  off'  as  quickly  as  possible, 
and  get  his  head  those  twelve  inches  lower  which  will 
give  him.  at  least  momentarily,  immunity  from  deadly 
danger." 


55 

Major  Knhn  slates:  "As  wasJjobe  expected,  the  ina- 
terigj_^amage  inflicted  by  artillery  on  field  works  proved 
a  negligible  quantity,  but  some  form  of  head  cover  was 
shown -to  be  ijecessai'yJto  give  protection  and  confidence 
to  tJTg  troops  when  long  exposedj^o  shrapnel  fire. 

"\\'hen  loopholes  were  used  in  field  works  they  were 
made  most  frequently  of  sand  bags  or  sod.  When  ax-ail- 
able,  brick  and  stone  were  also  employed. 

"At  Liaoyang  and  Haicheng  the  Japanese  trenches 
had  little  mounds  of  mud  on  the  superior  slope.  In  the 
absence  of  more  suitable  material  these  mud  mounds  af- 
forded a  simple  and  fairly  effective  form  of  head  cover." 

47.  A  background  for  the  heads  of  the  parapet  de- 
fenders would  usually  be  provided  by  the  natural  ground 
in  rear,  by  placing  the  parapet  somewhat  forward  of  the 
crest  of  the  hill.  Where  this  cannot  be  done,  it  may  be 
necessary  to  provide  it  artificiall}'. 

In  order  that  high  explosive  shells  may  not  injure 
the  defenders  who  are  manning  a  parapet  or  sitting  close 
behind  it.  it  is  necessary  that  there  should  be  nothing  in 
rear  to  catch  the  shell  and  explode  it  or  act  as  a  stop-butt, 
for  in  this  case  the  back-blast  or  all-around  effect  would 
cause  loss.  The  ideal  arrangement  would  be  to  have  the 
parapet  in  such  a  position  that  all  shells  just  missing  the 
crest  would  pass  clear  away  into  space.  But  this  could 
very  seldom  be  arranged,  as  it  would  usually  entail  trac- 
ing the  parapet  on  the  sky  line  when  viewed  from  the 
enemy's  position,  so  that  the  defender's  heads  would  be 
conspicuously  visible.  It  should,  however,  always  be  ar- 
ranged so  that  -there  is  no  steep  rising  ground  or  bank 
close  behind  the  parapet. 

For  this  reason  most  redouts  or  forts  are  regular  shell 


56 

traps  because  of  the  parados,  designed  to  protect  the  de- 
fenders of  the  gorge  of  the  redout  from  reverse  fire. 

48.  Arrangements  for  Fire  to  the  Rear. — In  the 
present  day  regular  closed  redouts  are  not  usuaily  re- 
quired, so  protection  to  the  defenders  of  the  gorge  is  un- 
necessary. If  it  is  desired  to  provide  a  firing  line  facing 
towards  the  interior  of  the  fortress,  it  should  be  at  a 
distance  off,  and  probably  on  the  reverse  slope  of  the 
hill,  or  in  some  other  place  hidden  from  the  front. 

If  a  closed  redout  is  constructed,  its  gorge  trench 
should  have  a  double  parapet ;  the  front  one,  serving  as  a 
parados,  should  be  kept  low^  and  used  as  a  firing  line  to 
command  the  interior  of  the  work,  in  case  the  enemy  gets 
in  over  the  front. 

If  the  trenches  are  in  such  a  position  that  there  is  a 
field  of  fire  to  the  rear,  they  may  be  arranged  for  fire  in 
that  direction.  The  profile  shown  in  fig.  12  may  be  so 
arranged  by  loopholing  the  reverse  parapet. 

49.  Overhead  cover  of  some  sort  should  always  be 
provided  unless  the  exigencies  of  time  prevent  it.  It  is 
not,  however,  necessary  that  this  shelter  should  be  of  a 
ver}'  massive  or  elaborate  description.  It  is  very  doubt- 
ful whether  it  would  ever  be  necessary  to  make  the  cover 
of  a  sufficient. strength  to  resist  bombardment.  It  is  evi- 
dent that  if  the  shelter  is  made  completely  underground 
and  the  earth  above  it  is  made  to  exactly  resemble  the 
surrounding  ground,  it  will  be  impossible  to  locate  its 
position,  or  to  drop  successive  shells  upon  it.  The  utmost 
it  would  have  to  fear  would  be  a  chance  hit. 

Splinter-proofs  should  satisfy  the  following  condi- 
tions : 

1.  They  must  not  cause  breaks  in  the  firing  crest, 
for  they  would  then  necessitate  an  increase  in  the  linear 


57 

development  of  the  trenches  for  a  given  number  of 
marksmen,  and  consequently  would  increase  the  labor  by 
a  considerable  per  cent. 

2.  They  must  be  capable  of  construction  after  the 
trenches  are  built,  without  requiring  any  considerable  re- 
adjustment of  the  work  already  done.  This  condition 
will  be  very  useful  when  it  is  not  possible  to  determine 
upon  the  time  available  for  fortifying  a  position,  when 
there  are  not  a  sufficient  number  of  workmen  to  make 
both  parapets  and  shelters  at  the  same  time,  and  when 
it  has  not  been  possible  to  get  together  the  necessary  ma- 
terials for  the  building  of  these  shelters  at  the  moment 
when  work  on  the  trenches  can  be  commenced. 

3.  They  must  permj^the  sheltered  men  to  come  out 
rapidly,  in  order  to  get  to  their  fightTng  posftions  behind 
the  firing  crest. 

4.  They  must  not  cause  any  projection  above  the 
parapet,  which  would  immediately  disclose  its  presence. 

The  shelter  may  be  small  in  area;  it  is  only  required 
to  accommodate  the  men  in  the  firing  line,  for  the  sup- 
ports should  be  in  another  shelter  in  rear.  If  time  and 
materials  do  not  admit  of  covered-in  shelters  being  pro- 
vided, a  deep,  narrow  trench  will  give  fair  security.  If 
the  earth  admits,  it  may  be  recessed  on  the  side  next  the 
enemy,  as  in  the  Boer  trench  (fig.  11,  E.  F.  AL). 

Fig.  12  shows  a  form  of  splinter-proof  which  may  be 
constructed  after  the  trench  is  completed,  and  gives  com- 
plete protection  to  men  firing.  (See  par.  111.) 

In  fig.  13  is  shown  a  splinter-proof  constructed  in  the 
trench  shown  in  fig.  3,  which  fulfils  the  above  condi- 
tions. 

Fig.  14  shows  a  splinter-proof  which  can  be  con- 
structed either  during  or  after  the  construction  of  the 


58 

trench  shown  in  fig.  3.  By  deepening  the  trench  as  shown 
by  the  dotted  hnes,  two  ranks  of  men  may  be  sheltered 
sitting,  facing  each  other;  see  par.  112.  (For  other 
forms  see  fig.  10  and  E.  F.  M.  firs.  34-43.) 

When  shelters  are  constructed  immediately  in  rear 
of  the  works,  in  order  to  prevent  their  being  hit  by  shots 
aimed  at  the  firing  trenches,  they  should  be  separated 
from  their  firing  trench  by  at  least  three  times  the  mean 
probable  error  of  the  pieces  having  the  greatest  error. 
This  error  may  be  assumed  as  about  50  yards  for  pieces 
in  use  today.  Therefore  shelters  must  be  established  at 
least  150  yards  from  the  work,  unless  local  conditions  and 
the  form  of  the  terrain  permit  this  distance  to  be  reduced. 
But  by  judiciously  placing  the  shelters  a  distance  of  even 
twice  the  probable  error  in  rear  of  the  firing  crest ;  that 
is,  100  yards,  the  probability  of  being  struck  by  shots 
aimed  at  the  crest  will  be  very  small. 

Another  method  often  preferable,  of  guarding  the 
splinter-proof  against  shots  aimed  at  the  trenches,  con- 
sists in  placing  it  a  little  to  the  rear  and  outside  of  the 
flanks.  It  is  evident  then,  in  this  case,  that  if  the  neces- 
sary precautions  are  taken  to  render  the  shelters  as  in- 
visible as  possible,  they  will  not  become  the  object  of 
special  fire,  and  they  can  be  placed  much  less  than  100 
yards  to  the  rear.  In  both  cases  it  will  become  necessary 
to  establish  covered  ways  between  the  shelters  and  the 
trenches.  This  latter  will  most  frequently  be  possible  only 
in  sieges. 

The  thickness  of  overhead  cover  for  splinter-proofs 
should  be  from  six  to  eight  inches  of  earth  on  a  support 
of  brush  or  poles  strong  enough  to  hold  it  up.  For  bomb- 
proofs  a  minimum  thickness  of  six  inches  of  timber  and 
three  feet  of  earth  is  necessary  against  field  and   siege 


59 

guns,  or  twelve  inches  of  timber  and  six  feet  of  earth 
against  howitzers  antl  mortars  of  a  heavy  siege  train. 
The  essential  thing  is  the  thickness  of  the  earth  layer, 
while  the  beams  serve  only  to  support  the  earth. 

In  determining  the  area  of  overhead  cover  to  be  pro- 
vided, allow  six  s(|nare  feet  per  man  for  occupancy  while 
on  duty  only,  or  twelve  square  feet  per  man  for  continu- 
ous occupancy,  not  of  long  duration.  For  long  occupa- 
tion eighteen  to  twenty  scjuare  feet  per  man  should  be 
provided. 

50.  Lookouts. — In  all  firing  trenches  provided  with 
overhead  cover,  some  form  of  lookout  must  be  provided 
to  enable  the  occupants  to  keep  informed  concerning  con- 
ditions and  mox-ements  in  their  immediate  front.  These 
lookouts  will  ordinarily  be  arranged  in  a  manner  similar 
to  loopholes  with  the  extra  condition  that  they  should 
give  as  extensive  a  view  over  the  foreground  as  possible. 

Major  Kuhn,  in  describing  the  Japanese  lines  north  of 
Mukden,  states:  "No  projections  are  allowed  above  the 
fire  crest  excepting  only  the  lookout  stations,  which  are 
located  on  the  most  commanding  points  a  few  yards  in 
rear  of  the  fire  trench.  These  are  made  bombproof  and 
kept  "as  low  as  possible  consistent  with  having  the  sight- 
ing slit  overlook  the  foreground." 

51.  Maga:;inc  accoininodatioii  is  not  necessary.  Rifle 
ammunition  is  best  placed  in  recesses  distributed  all  along 
the  front,  close  to  the  parapet,  and  these  would  be  re- 
plenished frcMii  an  intermediate  depot  in  rear  of  the 
works.  Artillery  ammunition  will  be  stored  near  each 
gun  emplacement. 

52.  The  trenches  and  shelters  should  be  in  short 
lengths,  particularly  if  oblique  or  enfilade  fire  is  to  be 
anticipated.     This  will  facilitate  their  adaptation  to  the 


60 

ground.  Lateral  communication  need  not  be  sacrificed 
by  this,  as  the  trench,  may  continue  round  a  piece  of 
natural  ground  left  as  a  traverse.  If  possible,  the  length 
of  any  distinct  independent  piece  of  trench  should  be 
such  as  to  be  suitable  to  be  garrisoned  by  a  distinct  unit, 
such  as  a  company,  platoon,  section  or  squad. 

53.     In  locating  a  line  of  trench  it  is  important : 

1.  To  avoid  a  sky  line. 

2.  To  occupy  the  military  crest  or  line  in  advance 
of  it. 

3.  To  preserve   communication  under  cover  with 
the  rear. 

The  selection  of  the  exact  position  of  infantry 
trenches,  how  far  forward  or  backward,  is  a  matter  of 
considerable  importance.  If  the  defensive  position  is  on 
a  hill  or  ridge  it  will  generally  be  difficult,  if  not  impos- 
sible, to  find  any  spot  at  or  near  the  top  where  all  the 
ground  in  front,  both  near  and  far,  may  be  seen,  except  in 
a  position  greatly  exposed  to  view  and  fire;  especially 
that  of  the  enemy's  artillery  located  behind  an  opposite 
ridge.  It  may  also  often  be  difficult  for  the  artillery  of 
the  defense  to  sweep  the  slopes  in  front  of  the  trenches, 
without  using  direct  fire  in  an  exposed  position.  (See 
par.  18.) 

Often  the  best  situation  will  be  at  the  bottom  of  the 
hill  slope,  at  or  near  its  junction  with  the  plain  in  front; 
from  these  a  grazing  fire  can  be  brought  over  the  plain, 
and  trenches  in  such  a  position  can  probably  be  well  con- 
cealed, and  it  may  be  difficult  for  the  enemy's  artillery 
to  reach  them. 

It  may  be  advantageous  to  give  two  lines  of  trench, 
one  low  down  the  hill,  as  above,  and  another  firing  over  it 
at  the  distant  ground  from  the  top  of  the  hill.     The  lat- 


61 

ter  may,  if  the  top  of  the  hill  is  wide  enough,  be  drawn 
well  back  from  the  actual  front  crest  of  the  hill,  and  this 
will  generally  assist  invisibility  (fig.  15).  This  retired 
position  would  have  a  further  advantage  in  that  its  sup- 
ports could  be  kept  close  up  in  rear  on  the  reverse  slope  of 
the  hill,  and  the  ground  in  front  of  the  trenches  could 
easily  be  swept  by  the  artillery  of  the  defense,  located  in 
a  sheltered  position  behind  a  hill  or  ridge  in  rear. 

If  there  is  timber  near  the  top  of  the  hill,  the  line 
may  be  located  in  it,  so  as  to  have  a  good  field  of  fire  and 
yet  not  be  exposed  to  artillery  fire  directed  at  the  front 
edge.     (See  par.  62.) 

54.  Field  of  Fire. — The  question  as  to  whether  the 
trenches  should  be  located  so  as  to  control  the  ground  at 
long  and  mid  range  or  at  short  range  is  important,  and 
no  single  rule  can  be  laid  down  for  all  cases,  as  the  proper 
solution  will  depend  not  only  upon  the  topography  of  the 
site,  but  also  upon  the  relative  proportions  of  artillery 
and  infantry  of  the  defense.  If  it  is  impossible,  on  ac- 
count of  accidents_of  the  ground,  to  keep  the  enemy  under 
fire_irQmJ.400  yards  in,  it  would  beadvTsable  to  use  the 
artillery  so  as  to  force  an  early  deployment,  and  by  lines 
of^skiimisher^  in  advanced  trenches,  so  situated  that  the 
men  can  be  withdrawn  without  difficulty  or  without  mask- 
ing the  fire  from  the  main  position,  delay  his  advance  as 
much  as  possible,  reserving  the  defense  from  mid  range 
in  for  the  main  line. 

It  will  seldom  happen  that  the  entire  field  of  fire  to  the 
limit  of  effective  range  can  be  completely  swept  from  any 
position  that  can  be  selected.  A  position  should  be  sought 
which  reduces  the  dead  spaces  to  a  minimum  in  number 
and  extent;  and,  if  possible,  advanced  or  auxiliary 
trenches  should  be  located  to  sweep  them.     If  the  ground 


62 

is  open  to  1,000  yards  or  more,  the  long  or  mid  range  is 
more  important  than  the  short  range,  for  an  effective  fire 
on  the  enemy  while  he  is  advancing  from  1200_ta_200 
yards  range  will  almost  certainly  put  him  out ;  or,  if  by 
any  chance,  he  arrives  at  200  yards  in  condition  to  keep 
on.  little  can  be  attained  by  holding  him  under  fire  from 
200  yards  in,  and  a  retirement  is  in  order,  unless  obstacles 
exist.  In  both  cases,  the  advantage  of  dead  space  in  the 
close  foreground  is  more  apparent  than  real,  and  the  main 
trenches  should  not  sacrifice  command  of  more  distant 
ground  within  effective  range,  in  order  to  sweep  the 
foreground.  Such  dead  ground  must  be  commanded  at 
night  or  in  thick  weather  by  trenches  detached  or  in 
flanking  relation. 

On  the  contrary,  if  an  enemy  can  approach  under 
cover  to  mid  range  or  less,  there  will  scarcely  be  time  to 
stop  him  by  fire  alone,  and  obstacles  are  desirable  at  close 
range,  which  must  be  commanded  by  fire.  The  trenches, 
in  such  cases,  must  be  advanced  to  cover  the  close  fore- 
ground, and  if  necessary  another  line  in  a  different  posi- 
tion established  to  sweep  the  more  distant  ground. 

55.  Coiniunnication  zvith  the  Rear. — There  is  one 
considerable,  difficulty  attending  the  location  of  lines  of 
parapet  in  a  forward  position  low  down  a  hillside,  and 
that  is  in  the  provision  of  concealed  means  of  access  to 
them  and  of  shelter  for  the  supports.  Where  the  works 
are  hastily  thrown  up  in  anticipation  of  an  early  attack, 
it  will  be  hardly  possible  to  provide  for  these  at  all,  and 
the  use  of  works  in  such  positions  should  in  such  circum- 
stances be  avoided  as  far  as  possible.  If  the  ridge  is  in- 
tersected by  ravines  or  covered  with  growth  through 
which  men  could  move  under  cover,  the  trenches  at  the 
foot  of  the  slope  can  be  easily  reinforced  and  should  be 
constructed. 


63 

Where  such  works  are  absolutely  necessary,  and  also 
in  cases  of  other  advanced  isolated  works  where  covered 
approaches  cannot  be  constructed,  the  defenders,  who 
must  be  in  more  than  the  usual  streng-lh,  must  take  their 
posts  under  cover  of  darkness,  and  must  take  with  them 
food,  water,  and  ammunition  for  the  whole  day ;  for  it 
will  be  impossible  to  reinforce  them  under  fire  or  to  re- 
lieve them  except  at  night. 

Where,  however,  the  works  are  constructed  some  time 
before  an  attack  is  expected,  oblique  approach  trenches 
can  often  be  provided,  and  this  should  be  done  wherever 
possible,  but  the  configuration  of  the  ground  may  some- 
times forbid  it.  Fig.  16  shows  a  typical  arrangement  of 
approaches  and  communications  from  the  support  to 
the  firing  trenches.  Fig.  17  shows  a  section  of  com- 
municating trench  ;  if  the  enemy's  fire  is  all  from  one 
side  but  one  bank  is  needed.     (See  paragraph  113.) 

Their  is  little  need  for  concealment  of  these  com- 
municating trenches,  for,  if  they  are  deep  enough  to  pre- 
vent tlie  enemy  from  seeing  whether  anybody  is  passing 
through  them,  he  cannot  afford  to  bombard  them  on  the 
mere  chance  that  there  may  be  somebody  there.  It  is 
only  to  prevent  their  betraying  the  position  of  the  firing 
trenches  that  it  is  advisable  to  have  them  inconspicuous. 
They  should  be  laid  out  so  as  to  take  advantage  of  all 
accidents  of  the  ground,  both  to  save  labor  and  to  secure 
invisibility. 

56.  Cover  for  Supports. — The  provision  of  suitable 
cover  for  the  supports  is  a  most  important  matter.  The 
best  place  is  on  the  reverse  slope  of  a  steep  hill.  When 
good  natural  coveixloes  not  exist,  it  may  be  necessary  to 
provide  artificial  splinter-proof  sliclter'^,  kept  low  and  well 


64 

concealed,  or  even  in  extreme  cases  to  provide  bomb- 
proofs,  but  the  latter  v^ould  only  be  necessary  where  the 
site  was  most  exposed  and  unsuitable  for  defense. 

The  supports  must  be  protected  against  the  fire  of 
the  artillery  up  to  the  moment  of  their  intervention,  and 
placed  so  that,  if  necessary,  they  can  reinforce  the  firing 
line  or  make  a  movement  to  the  front,  without  having  to 
suffer  greatly.  This  result  will  be  obtained  by  placing 
them  in  the  cover  trenches  constructed  at  least  100 
yards  in  rear  of  the  crest  of  fire,  either  opposite  the  inter- 
vals between  the  works  or  else  upon  the  flanks ;  and  by 
placing  part  of  these  trenches  prepared  for  firing,  so  that 
they  can  cover  the  intermediate  terrain  well  with  their 
fire  without  leaving  the  trenches;  or  by  abandoning  the 
trenches  in  order  to  make  a  move  to  the  front.  Under 
these  conditions  the  reinforcement  of  the  line  of  fire  will 
be  made,  if  there  is  occasion  to  make  it,  simply  by  pro- 
longation; whilst  that  of  the  counter  attack,  setting  out 
from  a  point  very  close  at  hand,  will  very  quickly  leave 
the  zone  bombarded  by  the  enemy's  artilleiy  after  he  ele- 
vates his  fire,  and  will  act  with  all  the  desirable  sudden- 
ness. 

Depending  upon  the  terrain  and  the  tactical  circum- 
stances, the  cover  trenches  of  the  units  in  reserve  can  be 
formed  either  into  a  single  line  or  in  echelon,  corre- 
sponding each  to  about  one  section.  They  should 
not  be  placed  one  behind  another,  as  that  would  increase 
their  chances  of  being  hit.  When  they  can  be  prepared 
with  light  splinter-proofs  of  the  type  mentioned  in  para- 
graph 49,  two  men  per  yard  of  length  can  easily  be  shel- 
tered. The  development  will  be  still  less  with  the  more 
elaborate  type  of  splinter-proofs. 

Major  Reichman  states:    "The  shrapnel  is  a  most  ef- 


-  n:o  —  -> 


Profile  Fi^.jO  E/evatior} 

Notched  Parapet  with  Splinter -Proof . 


,,^JJ?^^>//f//>//fi!. 


(''''-W/'^/////^  ^^Ao.» 


/.oophoJe  Cove?' 

Scale     g      »     't     18  14  lr,ch«« 


Fig.lZ 
Spli  Titer-  Proof 


Zo%t  Scale 


>  :^iWMV.M. 


(-3;o 


^.     ,^    SpU77ter-Proof5  .  ^.     _ 


Trencties  retired  dr?d  ,^dy<3r7ced 

Ir?  fa/?fry  Positions 
StiQwing  coTTf  mzinicatfor7s  ^itf?  supporfs 


67 

fectivc  and  deadly  projectile,  and  in  combination  with  its 
long-  range,  compels  all  to  hng  co\'er.  The  side  that  stands 
on_iIi£_defeniive_iiiust  have  very ^sjtibstantial  cover  if  it 
wishes  to^yoid  murderous  losses,  and  at  the  longer 
ranges  with  the  steep  angle  of  incidence  of  the  shrapnel 
the  reverse  slopes  of  hills  offer  little  protection.  It  is 
therefore  necessary  that  not  only  the  firing  line  on  the 
front  slopes  but  the  reserves  on  the  reverse  slopes,  be 
protected  by  suitable  cover." 

57.  The  drainage  of  defensive  works  that  are  to  be 
occupied  longer  than  a  day  is  of  great  importance  and 
should  be  provided  for,  as  otherwise  the  trenches  and 
works  may  be  so  flooded  by  storms  as  to  become  unten- 
able. The  drainage  problem  is  difficult  in  deep  trenches ; 
pumping-  may  have  to  be  resorted  to,  or  seepage  pits  dug. 
All  surface  drainage  into  trenches  should  be  cut  off. 

58.  Tclcplionic  couununication  should,  if  possible, 
be  provided  between  the  positions  of  the  supports  and 
each  of  the  principal  infantry  trenches  or  groups  of 
trenches,  and  also  to  the  post  of  the  section  commander 
in  rear.     (See  paragraphs  13,  24  and  76.) 

59.  Obstacles. — With  an  open  field  of  fire,  en- 
trenched troops  with  magazine  rifles  and  plenty  of  am- 
munition do  not  recjuire  the  aid  of  obstacles  to  enable 
them  to  stop  the  most  determined  attack.  Still,  they 
would  always  add  considerably  to  the  strength  of  a  posi- 
tion, and  there  may  be  places  where  obstacles  are  re- 
quired; namely,  where  the  work  is  retired  behind  the 
-military  crest  of  a  hill  so  that  the  field  of  fire  is  short,  or 

to  delay  troops  at  certain  points  where  a  heavy  fire  can- 
not be  brought  to  bear  on  them,  such  as  at  the  passage 
of  a  bridge  or  ford,  in  a  defile,  etc. 

Obstacles  are  designed  to  protect  the  works  from  sur- 


68 

prise  and  to  reduce  the  momentum  of  attack  by  breaking- 
up  the  enemy's  formation,  and  holding  him  under  the 
accurate  fire  of  the  defense.  They  shoukl  be  invisible 
from  the  direction  of  approach,  should  be  difficult  to  de- 
stroy, and  should  afford  no  screen  or  cover  to  the  enemy. 

Obstacles  should  be  placed  at  such  a  distance  in  front 
of  the  parapet  that  shots  directed  against  it  will  not  se- 
riously injure  them.  The  fire  of  guns  is  more  efficacious 
against  obstacles  than  that  of  howitzers  and  mortars; 
and  their  probable  mean  dispersion  is  about  30  yards. 
Consequently,  obstacles  ought  to  be  established  from  90 
to  100  yards  from  the  parapet,  and  never  less  than  60 
yards,  unless  covered  or  screened. 

This  distance  between  the  trenches  and  obstacles 
which  the  effect  of  the  artillery  fire  recjuires,  is  also  de- 
manded by  moral  considerations.  If  the  obstacles  are 
placed  too  near  the  trenches  the  defender  of  the  para- 
pet runs  great  risk  of  becoming  demoralized  by  the  ad- 
vance of  the  assailant,  whom  his  fire  cannot  stop,  even 
before  the  enemy  reaches  the  obstacles.  These  obstruc- 
tions will  then  be  useless.  They  should  always  be  so 
placed  as  not  to  interfere  with  the  execution  of  counter 
attacks.  They  should  usually  not  be  placed  at  a  distance 
from  the  firing  trench  greater  than  400  yards,  in  order 
that  the  defenders  of  the  trench  may  not  be  under  artil- 
lery fire  when  the  attacking  troops  reach  the  obstacle. 

If  on  the  line,  they  are  in  the  ditch,  if  there  is  one, 
or  are  employed  to  close  intervals,  and  are  flanlced  or  en- 
filaded by  adjacent  works. 

The  high  wire  entanglement  is  the  most  generally 
useful  of  all  obstacles,  because  of  its  effectiveness,  the 
rapidity  of  construction,  the  difficulty  of  removal,  the 
comparatively  slight  injury  from  artillery  fire,  and  its  in- 


69 

dependence  of  local  material  supplies.  In  woorled  coun- 
try abatis  or  slashings  would  generally  be  used.  (See 
E.  F.  M..  paragraphs  49-59.) 

60.  Clearing  the  foreground  in  front  of  the  infantry 
parapet  is  important,  but  of  course  it  will  generally  be 
impossible  to  get  rid  of  all  the  cover  within  effective 
range  of  modern  rifles.  As  much  as  possible  should, 
however,  be  done,  beginning  near  the  works  and  pro- 
ceeding outwards.  If  possible  the  clearance  sliould  ex- 
tend to  at  least  800  yards  from  the  parapet.  The  demoli- 
tion of  every  house  or  village  in  front  of  the  defender's 
works  is  not  so  important  nowadays  as  it  used  to  be;  the 
attackers  will  not  be  able  to  use  the  buildings  as  posi- 
tions for  their  infantry,  as  a  few  rounds  of  high  ex- 
plosive shell  would  bring  them  down  in  ruins  on  their  oc- 
cupants. They  should,  however,  be  removed  if  conceal- 
ment could  be  obtained  in  rear  of  them  for  the  attacker's 
columns. 

61.  HousCjS  or  znllagej_yvhich  exist  within  a  de- 
fensive line  will  seldom  be  of  any  use  from  a  defensive 
point  ofjview.  If  occupied  they  would  offer  most  easy 
targets  for  concentrated  artillery  fire,  and  the  destructive 
effect  on  buildings  of  modern  high  explosive  shell  is  so 
great  that^they-jazjoiild  bring  ruin  on  any jtraops  within 
them.  It  would  generally  be  safe  to  ignore  them  alto- 
gether, as  the  reasons  which  make  them  unsuitable  for 
the  defenders  to  occupy  would  also  make  them  objects 
of  little  temptation  to  an  attacker,  who  would  similarly 
be  unable  to  hold  them  under  the  defender's  fire.  If  it 
were  really  necessary  to  deny  to  the  attackers  tlie  ground 
occupied  by  buildings,  it  would  be  best  to  put  the  defend- 
ers in  trenches  outside,  well  clear  of  splinters  or  frag- 
ments of  stone,  but  in  a  position  to  bring  fire  over  the  ap- 


70 

proaches  to  the  buildings.  In  places,  however,  where 
artillery  could  not  be  brought  to  bear,  a  group  of  strong 
buildings  could  be  easily  made  into  a  strong  defensive 
position.  Isolated  walls  or  walled  enclosures  without 
roofs,  if  thick  enough  to  resist  rifle  fire  and  shrapnel  bul- 
lets, are  useful,  for  they  cannot  be  damaged  except  by 
a  direct  shell  hit,  and  even  then  only  a  short  length  will 
be  blown  down.  They  afford,  however,  a  good  target. 
(See  E.  F.  M.,  paragraphs  60-63.) 

62.  JVoods  are  not  generally  very  useful  under 
modern  conditions.  If  it  is  known  that  the  front  edge 
is  held,  so  good  a  target  is  afforded  that  a  very  heavy 
fire  can  be  concentrated  on  it.  The  interior  of  a  wood 
certainly  gives  concealment,  but  great  labor  is  involved 
in  preparing  a  defensive  position  there  and  forming  a 
field  of  fire,  obstacles,  and  communications.  Such  a  po- 
sition gives  no  fire  outside  the  wood  to  the  front,  unless 
the  wood  is  on  a  steep  slope ;  in  which  case  a  line  might 
be  located  in  the  wood  and  have  a  good  field  fire  to  the 
front.  If  a  wood  is  in  front  of  the  defensive  line,  its 
rear  edge  should  be  entangled  and  positions  taken  up 
from  which  a  fire  can  be  brought  to  bear  on  troops  issu- 
ing from  it.  Generally  speaking,  a  wood  in  a  defensive 
position  is  a  source  of  weakhessV'aiicPvvorks~sliould  be 
arranged  if  possible  to  bring  a  heavy^fire  OA-er^ie  ground 
in  front  of  them  so  as  to  prevent  the  enemy  from  getting 
into  them.  It  may  sometimes  be  possible  to  have  the 
front  line  of  the  woods,  or  a  position  just  outside  the 
front  edge,  prepared  for  defense,  with  the  defending" 
troops  kept  concealed  in  rear,  and  only  brought  up  when 
an  infantry  attack  develops,  and  the  enemy's  artillery 
fire  must  to  a  considerable  extent  cease.  Communica- 
tions will  in  such  cases  be  necessarv. 


71 

63.  Co)iccaliitcitt.—¥\Y(i,  when  its  effect  can  not  be 
seen  or  learned,  is  almost  certain  to  be  ineffective,  and 
may  be  merely  a  waste  of  ammunition.  If  the  target 
cannot  be  distinctly  seen,  it  is  correspondingly  difficult  to 
ascertain  the  eft'ect  of  fire  upon  it.  Concealment,  there- 
fore, offers  greater  protection  than  any  other  single  fea- 
ture, and  every  effort  should  be  made  to  obtain  it.  As  a 
result  there  is  no  longer  such  a  thing  as  a  normal  type 
of  trench ;  for  the  form  which  might  be  best  suited  to 
one  locality,  owing  to  color  of  soil,  configuration  of 
ground  and  character  of  vegetation,  might  be  very  con- 
spicuous and  wholly  inadmissible  at  another. 

Concealment  will  have  to  be  secured  in  each  case  ac- 
cording to  the  conditions  of  the  site  at  the  time.  It  is 
obvious  that  a  trench  in  a  landscape  of  green  would  have 
to  be  differently  treated  from  one  at  the  same  place  in 
the  late  fall  or  early  spring;  the  color  of  the  earth  might 
be  very  conspicuous  against  green,  but  difficult  to  see 
against  the  yellowish  brown  of  the  same  vegetation  when 
dead ;  the  similarity  of  color  would  be  stronger  still  in 
a  plowed  field. 

One  .of  the  best  means  of  concealment  is  the  suppres- 
sion of  the  exterior  slope.  With  the  profiles  given  in  our 
manuals,  especially  when  the  slopes  are  carefully  finished, 
the  parapet  is  visible  at  a  great  distance  by  the  simple 
difference  in  lighting  of  the  exterior  and  tlie  superior 
slopes,  and  of  the  adjacent  terrain.  With  a  verv  gentle 
slo])e  of  1  on  5.  or  better,  1  on  6,  that  is  to  sav.  a  con- 
tinuation of  the  superior  slope,  the  difference  in  lighting 
between  the  two  surfaces  is  suppressed,  and  furthermore, 
a  surface  is  made,  which,  leaving  the  general  surface  of 
the  earth  with  a  very  slight  angle,  has  a  luminous  value 
api)roximately  equal  thereto. 


72 

Objects  projected  against  the  sky  are  much  more 
distinctly  seen  than  when  viewed  against  a  background, 
other  conditions  being  equal,  and  any  location  which  will 
bring  the  trenches  or  guns  on  the  sky  line  should  there- 
fore be  avoided.  It  should  be  remembered,  however, 
that  the  sky  line  varies  according  to  the  observer's  posi- 
tion, and  that  the  one  of  importance  is  that  from  the 
enemy's  point  of  \'iew.  A  distant  background  tends  to 
render  a  trench  more  conspicuous  than  one  close  at  hand, 
and  a  trench  blending  with  its  immediate  vicinity,  may  be 
readily  recognized,  if  projected  against  the  different 
shade  or  degree  of  color  or  different  vegetable  growth 
of  a  distant  hill.  Where  the  condition  of  securing  a 
proper  field  of  fire  forces  the  trench  into  a  location  in 
which  sky  line  or  background  tends  to  make  it  difficult  of 
concealment,  it  may  be  rendered  inconspicuous  by  an 
artificial  background  or  a  slight  screen  in  front.  It 
should  always  be  borne  in  mind  that  a  man,  close  to  a 
screen  of  vegetable  growth,  can  see  what  is  on  the  other 
side  better  than  a  man  much  farther  away;  and  that  if 
he  is  immediately  behind  it,  he  may  have  almost  an  un- 
interrupted view,  even  though  it  be  thick  enough  to  form 
at  a  distance  a  nearly  complete  bar  to  vision.  In  con- 
structing artificial  backgrounds  or  screens,  care  should  be 
taken  to  have  them  appear  as  natural  features  of  the 
landscape,  otherwise  they  will  simply  serve  as  trench 
markers. 

Invisibility  is  ordinarily  increased  by  keeping  the 
parapet  as  low  as  possible.  Every  foot  that  the  com- 
mand is  increased  makes  it  harder  to  conceal  the  earth 
thrown  up.  In  endeavoring  to  keep  the  parapet  low, 
great  caution  must  be  observed  not  to  put  it  below  the 
height  demanded  by  a  proper  field  of  fire  over  the  fore- 


76 

ground,  and  this  can  be  determined  only  by  putting  tlie 
eye  at  the  same  height  that  the  soldier's  eye  will  be  in 
firing. 

Invisibility  is  also  increased  by  causing  the  parapet 
to  blend  in  with  the  landscape  as  much  as  possible;  this 
is  effected  by  various  means,  such  as  avoiding  all  sharp 
angles,  causing  the  ends  of  the  parapet  to  fall  away  grad- 
ually and  generally  avoiding  any  sudden  changes  in  direc- 
tion vertically,  covering  the  earth  thrown  up,  if  conspicu- 
ous, wath  material  which  will  conceal  its  color  and  cause 
it  to  resemble  immediate  surroundings,  etc. 

It  is  more  important  that  the  trench  be  screened  from 
artilleryTire  than  from  infantry  fire,  hence  efforts  should 
be  made  to  render  it  inconspicuous  from  the  position 
which  will  probably  be  occupied  by  the  enemy's  guns  or 
observers.  If  there  is  opportunity,  an  officer  should  be 
sent  to  these  points  to  find  whether  he  can,  with  a  field 
glass,  readily  see  the  trenches  or  not;  and,  if  they  are 
quite  discerned,  to  make  note  of  the  features  which  ren- 
der them  conspicuous,  whether  color,  shape,  projection 
against  sky  or  other  background,  etc.  It  is  more  im- 
portant to  conceal  the  trench  against  the  enemy's  artil- 
lery than  against  his  infantry,  because  the  artillery  can 
bring  a  shower  of  projectiles  upon  it  from  such  ranges 
that  the  infantry  rifle  is  helpless  in  reply,  while  against 
infantry  fire  of  the  attack,  which  must  be  delivered  in  the 
open,  the  trench  should  have  the  advantage.  If  the  trench 
can  be  made  inconspicuous  at  both  long  and  short  ranges, 
so  much  the  better ;  but  officers  should  remember  that  the 
appearance  at  100  yards  may  be  quite  different  from  what 
it  is  at  500  or  1,000  yards,  and  that  within  400  yards  ap- 
pearance matters  little,  as  the  enemy  in  attack  is  then 


74 

loo  close  to  change  his  formation  to  conform  to  what 
he  may  then  see. 

Major  Kuhn  states :  "At  Nanshan  the  parapets  of 
the  Russian  trenches  were  relatively  high  and  prominent. 
In  fact,  the  Russians  made  no  attempt  at  concealing  their 
trenches  in  their  positions  preceding  the  battle  of  Liao- 
yang,  and  their  works  were  conspicuous  on  the  bare  hill- 
sides. Even  at  greater  distances,  the  freshly  turned 
earth  and  prominent  profile  of  the  parapet  plainly  marked 
their  location.  At  Liaoyang  and  subsequently,  attempts 
at  concealment  by  covering  the  freshly  turned  earth  with 
sod  and  by  adopting  flatter  slopes  for  the  parapet,  became 
manifest. 

"When  practicable  the  Japanese  always  employed  ar- 
tificial concealment  for  their  trenches,  covering  the 
freshly  turned  superior  slope  with  millet  straw,  bean 
vines,  or  kaoling  stalks  gathered  from  adjacent  fields,  or 
even  planting  a  row  of  kaoling  stalks  in  an  upright  posi- 
tion. 

"In  the  matter  of  concealing  their  works  the  Japanese 
took  infinitely  more  pains  and  displayed  a  far  greater 
skill  than  the  Russians." 

Major  Judson  states :  "Thus  far  I  have  dwelt  upon 
the  principle  of  dispersal.  (See  paragraph  13.)  The 
other  principle  emphasized  in  this  war  was,  of  course, 
concealment.  By  every  artful  device  the  position  of  the 
defensive  units  must  be  kept  from  the  enemy.  The  works 
must  be  of  slight  profile  or  mainly  sunken.  Much  earth 
must  be  carefully  wasted  out  of  sight  of  the  enemy.  New 
earth  within  range  of  his  vision  must  be  sodded,  or 
planted  with  stubble,  to  resemble  neighboring  areas.  Ar- 
tillery positions  must  be  located  in  rear  of  crests,  villages 


75 

or  woods.  As  a  rule,  rather  tlian  as  an  exception,  artil- 
lery must  fire  over  infantry. 

"To  secure  concealment  and  a  proper  location  and 
dispersal  of  field  works,  obviously  no  special  rules  can 
be  laid  down.  In  each  case  what  is  required  is  an  appli- 
cation of  a  trained  common  sense  to  the  particular  prob- 
lem offered  by  the  terrain." 

64.  Diuiuiiy  TrciicJirs  or  Parapets. — In  case  con- 
cealment of  the  general  position  is  not  possible,  decep- 
tion must  take  its  place.  The  trenches  actually  occupied 
must  be  so  arranged  as  to  afford  concealment  of  the  in- 
dividual man.  and  dummy  tr^nchesr  pwrposely  made 
easily  visible,  may  be  arranged  to  draw  the  enemy's  fire. 

Dtmimv  trenches  should,  if  practicable,  have  head 
cover,  not  only  to  make  them  more  conspicuous,  but  also 
to  make  it  more  difficult  to  discover  whether  they  are 
occupied  or  not.  They  are  better  above  and  behind  the 
occupied  trenches,  if  the  lay  of  the  ground  permits.  The 
enemv  will  observe  that  fire  comes  from  the  direction 
of  the  dummies  and  will  conclude  that  it  comes  from 
them.  Fire  directed  on  the  dummies  will  pass  o^•er  the 
heads  of  the  defenders,  a  condition  preferable  to  shots 
falling  short,  which  would  be  the  result  of  dummies  in 
front  of  the  occupied  trenches. 

It  is  obvious  that  dummy  trenches  should  be  placed 
at  such  distance  from  the  real  trenches  as  not  to  bring 
the  latter  within  the  fire  which  they  may  attract. 

The  Russians  in  Manchuria  in  some  instances  made 
a  line  by  turning  two  or  three  furrows  with  a  pl(jw  which 
looked  at  a  distance  like  the  parapet  of  a  trench ;  and 
where  they  covered  these  furrows  with  grass,  which  soon 
dried,  the  effect  of  an  imperfect  concealment  was  strong. 


76 


CHAPTER  V. 
Artillery  Positions. 

65.  Low  commands  and  inconspicuousness  are  to  be 
sought  for  in  the  location  of  artillery  emplacements,  and 
they  must  be  suitable  for  pieces  on  traveling  mountings. 
(See  paragraph  18.) 

Concealment  of  position  is  most  desirable,  whether 
artificial  or  natural  cover  is  used,  therefore  sky  line  crests 
without  cover  are  generally  forbidden.  It  is  quite  as 
bad,  if  not  worse,  to  take  position  on  the  reverse  slope, 
where  an  enemy  can  easily  range  to  the  top,  and  then 
proceed  to  sweep  the  slope  beyond.  Without  making  the 
mistake  of  moving  too  far  back,  it  is  nevertheless  ad- 
visable to  make  it  from  100  to  300  yards,  the  ideal  posi- 
tion being  behind  a  crest  of  another  similar  height 
some  distance  in  rear.  The  enemy  would  naturally 
be  deceived  as  to  the  result  of  his  shots  going  behind  the 
first  crest.  To  be  sure  artilley  creates  so-called  "dead 
spaces"  in  taking  such  positions,  but  they  must  be  cross- 
fired  by  units  dispersed  elsewhere.  An  intelligent  dis- 
persion of  the  units,  moreover,  diminishes  the  enemy's 
fire  and  increases  his  difficulties  of  adjustment.  (Sec 
paragraph  15.) 

In  taking  position  behind  a  crest,  a  defilade  of  1 5  feet 
is  necessary  for  the  concealment  of  the  gun  flnsli. 

The  maximum  effective  ranges  of  field  and  siege 
artillery  may  be  taken  as  follows : 

3-inch  field  gun 6,500  yards 

4.7-inch  siege  gun 7,600  yards 

6-inch  siege  howitzer 7,600  yards 

6-inch  siege  mortar 5, 500  yards 


77 

Major  Kuhn  states:  "At  Port  Artlnir  the  Russians 
made  the  mistake  of  placing-  batteries  upon  the  highest 
and  most  conspicuous  places,  which  became  ensy  marks 
for  the  Japanese  batteries  skilfully  located  in  the  in- 
equalities of  the  floor  of  the  valley  fronting-  the  Russian 
hills.  In  the  later  stages  of  the  siege  the  Russians  be- 
came wiser  and  some  of  their  later  batteries  were  most 
skilfully  located,  depending  upon  indirect  fire,  which 
latter  can  now  be  very  well  controlled  and  directed." 

66.  Form  of  Emplacement. — Na  £orm  ai^iege  bat- 
tery will  give  protection  from  howitzer  or  mortar  shells ; 
all  that  can  be  don^is  to  surround  tlie_  gun  platforms 
with  splinter-proof  walls  to  keep  out  frao-ments  of  shells 
which  burst  outside  the  emplacement.  (See  figure  118, 
E.  F.  M.) 

If  the  battery  is  in  so  retired  a  position,  or  so  well 
concealed  by  intervening  high  ground,  woods,  etc..  that 
it  cannot  be  seen  from  any  part  of  th.e  besieger's  position, 
and  observation  of  fire  on  it  is  impossil)le,  then  it  is 
hardly  necessary  to  have  even  splinter-proof  walls,  for  a 
shell  could  only  be  dropped  in  the  neighborhood  of  the 
emplacement  by  chance.  If,  on  the  other  hand,  the  em- 
placement was  anywhere  visible,  these  walls  would  form 
too  conspicuous  a  target. 

Emplacenienls^for  direct_^re_glms^_wl^ich^^^^  be 
in_positions  visible  _to  the^  enemy,  would  have  to  be  con- 
cealed by^  sinking  them  into  the  ground,  and  having  a 
background  of  trees  or  rising  ground  in  rear.  Iimsi- 
bility  for sucli  pieces  is  a  matter  of  supreme  importance, 
provided,  of  course,  that  range  and  field  of  fire  are  not 
sacrificed. 

Where  the  emplacements  are  liable  to  shrapnel  fire, 
some  form  of  cover  for  the  detachments  should  be  pro- 


78 

vided.  This  may,  in  the  case  of  field  defenses,  consist 
of  two  deep  pits  close  against  the  front  parapet,  one  on 
each  side  of  the  gun,  similar  in  principle  to  those  in  the 
ordinary  type  of  field  gun  emplacement,  but  larger  and 
deeper.  (See  figure  18.)  Or  overhead  splinter-proof 
cover  may  be  provided  at  the  sides  of  the  emplacements, 
or  in  the  traverse,  where  such  exists,  between  a  pair  of 
emplacements. 

67.  Positions  for  Liglif  Guns. — :It  would  not  as  a 
rule  be  necessary  to  provide  any  works  for  the  light 
rapid-fire  armament  or  for  the  field  guns.  The  essence 
of  the  employment  of  pieces  of  this  nature  is  surprise  and 
mobility,  so  that  there  should  be  nothing  that  will  mark 
the  positions  from  which  they  will  open  fire.  If  any 
form  of  protection  is  required,  field  q}aulments  can  be 
made  when  wanted. 

Guns  firing  by  indirect  fire  will  be  behind  natural 
screens,  such  as  a  hill,  woods,  etc.,  and  usually  will  not 
need  a  parapet  for  protection.  If  by  any  chance  the 
enemy  should  ascertain  their  position  closely  enough  to 
make  it  uncomfortable  or  dangerous,  they  can  ordinarily 
be  shifted  to  some  other  place  without  detriment  to  their 
own  fire. 

When  engaged  wTdi_direct  fire,  guiis^^ven  though 
provided  with  shields,  will  need  some  screen  or  protec- 
tion. When  the  ground  is  soft  and  no  naturaFcover  ex- 
ists, guns  are  best  protected  by  being  sunk  in  pits  or 
placed  behind  epaulments.  The  smallest  mound  in  front 
of  a  gun  will  stop  the  bullets  which  could  strike  the  gun 
crew  in  great  numbers,  by  ricocheting  under  the  shields. 
A  larger  parapet  could  almost  completely  place  the  ar- 
tillery under  shelter  from  any  percussive  fire  that  the 
enemy  would  try  against  it.     Moreover,  in  doing  this  the 


79 

artillery  will  not  lose  any  of  its  mobility  if  it  is  well  un- 
derstood that  it  must  not  consider  itself  as  any  more 
anchored  to  an  artificial  cover  than  it  would  be  to  a  nat- 
ural one,  which  it  certainly  would  not  hesitate  to  make 
use  of  on  such  an  occasion. 

Figure  18  shows  a  type  of  gun  pit  with  the  caisson 
body  alongside  the  gun.  The  pits  on  each  side  may  be 
provided  with  splinter-proof  cover  of  the  type  shown  in 
figure  12,  if  time  permits.  (See  paragraphs  111  and 
114.) 

Figure  19  shows  a  section  through  a  gun  pit  for 
direct  fire  behind  the  crest  of  a  hill.  Figure  20  is  a  sec- 
tion through  a  gun  pit  for  indirect  fire. 

68.  Indirect  Fire. — The  distance  that  field  guns  us- 
ing indirect  fire  can  take  position  below  the  crest  of  a 
hill  is  shown  approximately  in  the  following  table : 


Ranges 

At  50  yds. 

75  yds. 

100  yds. 

200  yds. 

300  yds. 

500  yds 

Yards 

Feet 

Feet 

Feet 

Feet 

Feet 

Feet 

lOOO 

10 

13 

16 

1500 

10 

19 

26 

38 

2000 

II 

15 

29 

41 

66 

2500 

10 

16 

21 

40 

58 

3000 

13 

30 

27 

53 

77 

3500 

17 

25 

33 

66 

4000 

21 

31 

41 

The  following  table  will  also  assist  in  the  location  of 
field  guns  for  indirect  fire,  and  in  determining  the  pro- 
tection afforded  by  reverse  slopes  to  supports  and  re- 
serves : 


80 


ANGLES  AND  SLOPES  OF  DEPARTURE  AND   FALL 
OF  SHRAPNEL. 

From  Field  Gtins. 


Ranges 

Departure 

Fall 

Yards 

Angle                 Slope 

Angle 

Slope 

500 

o°32' 

1 

TT5 

o°35' 

1 

TC5 

1000 

i°ii' 

1 
5W 

l°2Y 

1 

1500 

i°59' 

] 
25 

2°38' 

1 

31 

2000 

2°sY 

^V 

4°o8^ 

1 

2500 

4°02' 

t\ 

5°49^ 

l^TT 

3000 

5°I2^ 

1 
TT 

7°4i' 

1 

7.5 

3500 

6°2g^ 

1 

9°44^ 

1 

6 

4000 

i°W 

T^o 

I2°03' 

i 

4500 

9°28' 

i 

I4°37^ 

i 

5000 

II°IO^ 

i 

i7°26^ 

^^.^ 

5500 

i3°oi' 

1 

20°29^ 

^S 

6000 

I5°02^ 

\ 

23°4i' 

i.^ 

6500 

I7°i3^ 

i-z 

2  7°07^ 

i.^ 

The  dispersion  due  to  the  explosion  of  the  shrapnel 
shell  increases  the  angle  of  fall  of  some  of  the  bullets  at 
3,000  yards  to  about  18°,  or  1  on  3. 

69.  Expense  magazines  for  at  least  two  days'  sup- 
ply of  ammunition  are  required  in  the  neighborhood  of 
each  battery  or  group  of  emplacements.  They  should 
generally  be  on  the  flank  of  the  battery,  conveniently 
close,  and  connected  by  a  trench  to  give  covered  approach. 
Recesses  or  benches  for  a  few  rounds  of  ammunition 
should  be  provided  in  each  emplacement. 

70.  Means  of  access  to  the  emplacements,  to  enable 
the  pieces  to  be  brought  in  or  taken  out,  is  very  neces- 
sar\\ 

71.  Every  battery  or  group  of  emplacements  re- 
quires  an  observing  station,  which  should  be  on  com- 


81  . 

niandjng:  gTjpimd  ffihenc£__all  objects  to  be  aimed  at  can 
be  seen.  They  need  not  be- neaT_the_battery  i f  telephonic 
communication  is  provided.  They  should  be  as  incon- 
spicuous as  possible.  A  type  used  at  Port  Arthur  is 
shown  in  figure  21.     (See  paragraph  115.) 

72.  Captive  Balloons. — In  case  there  are  many  of 
the  enemy's  batten.^  positions  which  cannot  be  seen  from 
any  of  the  sites  available  for  observing  stations,  it  may 
sometimes  be  possible  to  make  use  of  captive  balloons. 
(Sec  paragraph  6.) 

7Z.  Eniplaccincnt  for  Machine  Guns.  —  In  the 
Japanese  lines  north  of  Mukden,  mftebine  guns  emplace- 
ments were  introduced  along  the  parapet,  their  dimen- 
sions being  8  feet  wide  by  10  feet  deep  by  3  feet  6  inches 
high,  with  splinter-proof  cover  about  18  inches  thick. 

An  emplacement  for  two  machine  guns  is  shown  in 
figure  22.  When  there  is  time,  splinter-proof  cover  of 
the  type  shown  in  figure  12  may  be  added.  Loopholes 
should  usually  be  provided,  and  in  case  they  limit  the 
sector  of  fire  too  much,  provision  can  be  made  for  raising 
the  guns  to  fire  over  the  crest  by  means  of  sand  bags 
stored  in  the  trench.  It  is  usually  best  to  emplace  two 
gunsjogether.     (See  paragraph  116.) 


'JU^XWJ" 


v---  12:0     -  -  1 


Plan 


(-3,oy 


QuTi  -Pit    SQctiorj  C-D 


Section  A-B 


r,j      .  c-      ■  Russia r?    Obserya?c  Statioti 

P/s/f  of    Framt.no  ^ 


frl.o) 


'.  < 

',1 

1 

n 

1 

1 

n 

F--  li^    -  H 

-  .40  -« 

B  'D 

Plan 


Fig  22 


Emplacement  for  Z  Mac/jure  Guns 


85 


CHAPTER  VI. 
Auxiliary  Means  of  Defense. 

74.  Electric  searchlights  will  play  a  most  useful 
part  in  defense  operations  of  the  future.  Not  only  will 
they  be  a  protection  against  night  attacks,  but  also  by 
their  use,  sapping  or  the  execution  of  trench  work  by 
the  enemy  at  night,  at  short  and  medium  ranges,  should 
be  rendered  impossible.  They  would  be  particularly  use- 
ful in  conjunction  with  light  rapid-lire  guns  or  pom- 
poms, or  with  machine  guns,  as  with  such  weapons  a 
heavy  fire  could  be  immediately  developed  on  the  object 
illuminated  by  the  beam.  The  position  of  the  beam  in 
relation  to  the  guns  should  be  well  to  one  side,  for  the 
best  position  for  seeing  illuminated  objects  is  for  the 
observer  or  gun-layer  to  have  his  line  of  sight  more  or 
less  at  right  angles  to  the  beam.  It  would  be  much  bet- 
ter if  the  lights  were  not  in  fixed  emplacements,  as  this 
would  tie  them  to  one  spot;  moreover,  the  emplacements 
would  be  conspicuous,  and  would  be  seen  by  day  and 
wrecked.  They  should,  therefore,  if  possible,  be  on 
traveling  mountings,  so  as  to  be  used  from  any  infantry 
parapet  or  from  the  open.  It  is  very  difficult  to  hit  a 
searchlight  at  night,  owing  to  the  impossibilitv  of  telling 
the  range  or  observing  the  fire.  If  in  addition,  its  posi- 
tion is  constantly  varying  it  would  be  much  more  dit- 
ficult  to  hit. 

75.  Interior  Coviiiiuiiications. — The  most  important 
features  of  a  fortress,  or  great  defensive  position,  are  the 
interior  communications,  and  these  should  be  the  first  of 


86 

the  -works  commenced  in  preparing  a  place  of  defense. 
In  laying  out  the  communications,  regard  must  be  had 
to  the  probable  tactical  organization  of  the  defending 
force.  It  is  desirable  to  have  a  road  or  roads  from  the 
headquarters  of  each  section  to  the  different  main  sup- 
porting points  in  that  section,  also  a  road  from  the  town 
or  general  headquarters— that  is  to  say,  from  the  main 
supply  and  ordnance  depots — to  each  sectional  headquar- 
ters. In  addition  to  these  radial  roads  there  must  be  a 
road  or  railroad  all  around  the  circumference  of  the  posi- 
tion in  the  rear  of  the  works.  It  is  most  necessary  that 
the  communications,  particularly  the  circumferential  ones, 
should  be  screened  from  the  enemy's  view. 

The  movement  of  troops  being  the  principal  element 
of  success,  the  communications,  and  especially  those 
which  must  assure  the  execution  of  counter  attacks  or  of 
offensive  returns,  have  a  prime  importance.  These  lines 
of  communication  should  be  so  placed  as  to  be  defiladed 
as  far  as  possible,  and  so  that  they  can  be  utilized  during 
the  whole  course  of  the  combat. 

76.  Telegraphic  and  Telephonic  ComiiiiDiicatioii 
should  be  provided  between  all  parts  of  the  position; 
that  is,  from  the  fortress  headquarters  to  each  sectional 
headquarters,    and    thence    to    each    important    work    or 

.group  of  works  in  the  front  line,  and  also  to  the  artillery 
commander's  posts.      (See  paragraphs  13  and  58.) 

77.  The  water  supply  of  a  fortress  is  a  most  im- 
portant matter.  It  is  obviously  necessary  that  the  place 
should  not  be  dependent  for  this  essential  requirement 
upon  an  outside  source.  If  its  supply  is  by  means  of  a 
conduit  or  pipe  from  a  distance  it  is  extremely  possible 
that  the  besiegers  will  find  and  sever  it.  It  is  most  neces- 
sary, therefore,  that  for  war  times,  at  all  events,  it  should 


be  possible  to  obtain  a  sufficient  supply  for  the  garrison 
and  the  civil  population  from  sources  within  the  defended 
area ;  that  is  to  say,  from  wells.  A  considerable  economy 
can  generally  be  effected  by  restricting  the  use  of  the 
pure  water  to  drinking  and  cooking  only,  and  there  will 
usually  be  streams  or  rivers  whence  water  for  washing 
and  cleaning  can  be  obtained.  If  the  only  supply  is  from 
a  river,  it  will  be  necessary  to  take  steps  to  sterilize  the 
water  by  boiling  or  otherwise,  before  it  is  issued  to  the 
troops  for  drinking. 


CHAPTER  VII. 
Strength  of  Garrison. 

78.  The  following  considerations  will  have  to  be 
taken  into  account  in  detcnniniiig  flic  nuinhcr  of  men  per 
yard  necessary  for  an  efficient  defense : 

1.  The  enemy's  strength  and  armament. 

2.  Whether  the  position  is  circular  or  crescent 
shaped,  so  that  reinforcements  from  the  center  can 
be  rapidly  sent  to  any  desired  point.  Or  if  it  forms 
a  long  line  with  slightly  or  no  refused  flanks,  and  if 
so,  whether  means,  such  as  railways  or  good,  con- 
cealed roads,  exist  by  which  reinforcements  may  be 
despatched. 

3.  Nature  of  the  ground  and  artificial  improve- 
ments; that  is,  if  good  cover  is  obtainable,  if  good 
communications  exist,  if  the  position  is  hastily  in- 
trenched, or  deliberately  prepared  for  defense. 

4.  Character  of  defense ;  that  is.  whether  or  not 
an  offensive  return  is  contemplated,  and  length  of 
time  the  defense  is  to  be  maintained. 

79.  When  a  force  is  suddenly  compelled  to  occupy 
a  defensive  position,  with  opportunity  to  make  only  the 
most  hastv  form  of  intrenchments,  no  fixed  or  even  ap- 
proximate rule  for  determining  the  number  of  men  per 
yard  of  front,  is  possible.  The  number  per  yard  of  front 
held  at  the  commencement  of  the  engagement  would  at 
times  be  greater  than  in  the  attack,  as  in  the  defense 
much  greater  depth  of  formation  is  necessary,  and  the  re- 
serve bears  a  larger  proportion  to  the  whole  force.  _Thus 
three  or  four  men  per  yard  of  front  might  be  required. 


89 

80.  When  from  tivelve  to  twenty-four  ivorking 
hot4rs_w^^ht  available  for  preparing  a  position  for  de- 
fense and  no  offensive  return  is  contemplated,  the  num- 
ber of  men  per  yard  of  front  can  be  considerably  reduced. 

81.  For  positions  elaborately  fortified,  having  a  cir- 
cular form,  the  number  of  men  per  yard  could  be  very 
small,  but  as  such  positions  would  only  be  prepared  where 
a  continued  defense  was  required,  an  increase  in  the  num- 
ber of  men  per  yard  of  front  would  be  necessary  to  en- 
able casualties  to  be  replaced. 

82.  In  estimating  the  strength  of  garrison  necessary 
for  a  carefully  prepared  defensive  position,  the  best  meth- 
od is  to  begin  with  the  infantry,  taking  each  section  of 
the  defensive  area  separately.  The  garrison  of  the  works 
can  be  calculated  with  fair  accuracy  by  measuring  the 
actual  length  of  the  lines  of  infantry  parapet,  and  allow 
not  less  than  two  men  for  each  yard.  Of  this  number 
about  one-fourth  should  usually  be  in  the  supports  and 
one-half  in  the  section  reserve.     (See  paragraph  13.) 

83.  The  strength  of  the  artillery  may  be  estimated 
at  thirty  men  per  medium  and  heavy  gun  (three  reliefs 
of  ten)  and  eighteen  men  per  light  rapid-fire  gun.  If 
available,  some  field  artillery  with  the  section  reserves 
will  often  be  useful.  The  engineers  should,  if  possible, 
be  not  less  than  one-twentieth  of  the  strength  of  the  in- 
fantry. 

84.  The  strength  of  the  general  reserve  would  de- 
pend mainly  on  the  facilities  that  are  likely  to  be  obtained 
for  active  measures.  It  is  desirable  to  have  it  equal  in 
strength  to  the  total  of  the  section  garrisons;  and,  in  any 
case  if  possible,  not  below  half  that  strength.  Mounted 
troops  and  field  artillery  would  be  usefully  employed  with 
this  reserve  if  the  defended  area  is  a  large  one. 


90 

85.  The  following  examples  serve  to  show  to  what 
extent  local  conditions  govern  each  particular  case : 

At  Plevna  in  1877,  where  all  the  defenses  were  con- 
structed after  the  first  Russian  attack,  the  Turkish  garri- 
son during  the  investment  numbered  1,875  men  per  mile 
of  perimeter  of  defense,  or  about  one  per  yard.  The 
place  was  held  for  five  months  and  resisted  all  the  Rus- 
sian attacks. 

At  San  Juan,  Cuba,  on  July  1,  1898,  the  Spanish 
force  of  1,197  men  held  a  line  about  one  and  one-half 
miles  long,  of  no  great  natural  strength,  and  not  care- 
fully prepared  for  defense,  nearly  all  day,  against  the 
American  force  of  8,412  men;  and  inflicted  a  loss  of 
1,156  in  killed  and  wounded. 

At  Nanshan  Hill  in  the  Russo-Japanese  War,  the  Rus- 
sian force  of  18,000  men  and  55  guns  held  the  position 
for  a  day  against  the  Japanese  force  of  42,000  men  and 
216  guns.  The  position  was  an  ideal  one  for  defense, 
being  a  hill  400  feet  high,  .which  rose  in  the  midst  of  a 
peninsula  only  two  miles  wide.  It  had  been  carefully 
prepared  for  defense.  The  actual  garrison  of  the  hill 
was  only  one  regiment.  Two  assaults  were  repulsed  and 
the  third  succeeded  because  the  Russians  had  not  ex- 
tended their  lines  of  obstacles  far  enough  into  the  sea, 
and  did  not  bring  up  their  reserves. 

At  Port  Arthur  in  1904,  there  were  4,755  men  con- 
centrated along  the  assailed  front  of  two  and  one-third 
miles,  and  7,730  men  on  the  unassailed  front  of  ten  and 
two-thirds  miles.  The  reserve  of  the  attacked  front  con- 
sisted of  406  men;  the  reserve  of  the  unattacked  front 
of  496  men,  and  the  general  reserve  of  510  men.     Con- 


91 

sequently  there  were  2.038  men  per  mile  on  the  attacked 
front,  or  1.16  per  yard.  On  the  unattacked  fronts  there 
were  725  men  per  mile,  or  0.41  per  yard.  (See  the  last 
part  of  paragraph  45.) 


92 


CHAPTER  VIII. 

Defense  of  Small  Isolated  Posts  Occupied  by 
Detachments. 

86.  The  foregoing  has  dealt  mainly  with  the  ca'se 
of  a  fortified  position,  held  by  at  least  an  independent  bri- 
gade, and  liable  to  be  attacked  in  force;  a  situation,  in 
fact,  which  would  probably  be  met  with  at  points  of  stra- 
tegical importance. 

87.  At  places  where  only  a  small  force  would  be 
available  for  the  defense,  certain  modifications  would  be 
necessary.  In  such  a  case  so  extended  a  line  could  not 
be  taken  up,  so  it  would  be  impossible  to  have  the  de- 
fensive line  so  far  out  as  to  keep  the  enemy  beyond  bom- 
barding range  of  the  town,  and  the  supporting  points 
would  probably  be  closer  together.  The  general  prin- 
ciples and  methods  of  defense  would,  however,  be  sim- 
ilar to  those  already  described,  subject  to  such  modifica- 
tions as  the  altered  conditions  would  require. 

88.  The  case  would  be  different  when  the  position 
was  quite  a  small  one  to  be  held  by  a  small  isolated  de- 
tachment, as  might  exist  for  the  defense  of  a  bridge,  or 
a  post  on  a  line  of  communications,  on  which  an  attack 
in  great  force  or  a  very  prolonged  siege  was  not  antici- 
pated. In  such  a  case  a  widely  extendedTiJOsTTion,  made 
up  of  supporting  points  at  intervals,  would  be  impos- 
sible. The  smalhiess  of  the  defending  force  would  neces- 
sitate its  remaining  more  or  less  concentrated. 

89.  Instead  of  providing  a  continuous  redout  or 
fort,  it  would  be  better  to  construct  simple  trenches  or 


93 

para^ets^'m  such  a  manner  as  to  in^rfere  as  little  as  pos- 
sible with  the  natural  appearance  of  the  gfotind ;  in  fact, 
to  rely  on  skilful  treatment  of  the  natural  features  of 
the  position  selected. 

90.  An  isolated  position  of  this  nature  would  have 
to  be  prepared  for  aU-aromid  oftac^y~^o~^^eme  of  the 
trenches  and  emplacements  would  be  required  to  face 
to  the  rear,  and  care  would  have  to  be  taken  to  avoid  the 
possibility  of  receiving  fire  in  reverse.  Shelters  for  the 
reserves  would  be  necesary  in  some  central  part  of  the 
position,  and  this  should  be  boJiib-proof  if  possible,  and 
in  any  case  well  concealed.  Shelters  for  storage  of  sup- 
plies, ammunition,  etc.,  would  be  required,  and  the  im- 
portant question  of  water  supply  must  not  be  overlooked. 

91.  The  position  selected  for  defense  would  not  in 
such  a  case  necessarily  contain  within  itself  the  object  to 
he  defended.  It  would  hardly  ever  be  possible  to  find  a 
position  that  could  be  defended  by  a  small  force  immedi- 
ately round  the  object,  if  the  latter  were  a  bridge,  rail- 
way station,  or  place  of  that  nature;  it  would  usually  be 
sufificient  if  the  position  commanded  the  object  and  the 
approaches    at    short    ranges.      Sometimes    it   might    be 

'necessary  to  make  the  defenses  in  the  form  of  two  posi- 
tions supporting  each  other,  and  both  commanding  the 
object. 

92.  //  the  enemy  is  uncivilized  or  unprovided  zvith 
artillery  it  is  evidently  unnecessary  to  employ  the  elab- 
orate methods  necessary  against  civilized  enemies.  Pro- 
tection against  rifle  bullets  is  easily  obtained,  and  neither 
concealment  nor  overhead  cover  are  in  such  cases  neces- 
sary. Blockhouses  and  villages  or  strong  buildings  make 
good  defensible  positions  in  these  cases.    For  the  methods 


94 

of  preparing  these  see  E.  F.  M.,  paragraphs  46,  61,  62 
and  63. 

For  a  fortified  post  in  a  savage  country  a  material 
obstacle  is  generally  essential;  so  if  the  work  itself  does 
not  provide  one  in  the  form  of  a  wall  or  stockade,  a 
strong,  independent  one  in  the  shape  of  barbed  wire  en- 
tanglements or  abatis  should  be  provided.  A  clear  field 
of  fire  is,  of  course,  imperative,  and  flank  defense  should 
be  provided,  dead  angles  being  inadmissible.  Every  fort 
of  this  nature  should  be  self-contained;  that  is,  should 
contain  room  for  storage  of  supplies  and  ammunition, 
and  should  be  possessed  of  its  own  water  supply. 


95 


CHAPTER  IX. 
Fortifications  on  the  Offensive. 

93.  Fortified  positions  will  be  used  in  the  field  by 
armies  on  the  offensive  as  well  as  on  the  defensive.  The 
fortifications  erected  by  the  former  will  generally  be  of  a 
hasty  and  slight  character,  thrown  up  by  its  outposts  for 
protection  against  sudden  attack,  and  for  the  purpose  of 
holding  the  ground  then  occupied,  but  soon  to  be  aban- 
doned in  an  advance  movement. 

Those  used  by  the  latter  will  often  be  of  the  character 
just  described,  if  the  army  is  advancing  or  retreating,  but 
in  retreat  it  may  also  make  use  of  positions  carefully 
selected  and  strongly  fortified,  previous  to  the  arrival  of 
the  main  body  of  the  army. 

94.  Fortifications  will  also  be  used  by  both  armies 
on  the  battlefield  \.o  enable  the  lines  tohold  the  positions 
they  may  occupy  at  the  time,  and  such  works  will  be 
thrown  up  after  the  beginning  of  the  engagement.  The 
same  body  of  troops  may  create  two  or  more  lines  of 
trenches  or  breastworks  in  a  single  day  as  it  advances  or 
falls  back;  the  works  must  necessarily  be  of  slight 
strength  at  first,  but  if  the  troops  remain  undisturbed  for 
a  few  hours  the  line  may  become  strong.  This  method 
of  fortification  was  carried  to  a  highei^  degree  of  per- 
fection in  the  Uivil  War  of  1861  to  1865  than  it  ever  was 
before  or  has  been  since;  as  owing  to  the  length  of  that 
conflict,  the  soldiers  learned  to  appreciate  the  value  of 
the  spade  to  an  extent  that  no  amount  of  peace  instruc- 
tion or  drill  can  equal.  The  battle  of  the  Wilderness  is 
a  good  illustration  of  this  fortification  of  the  battlefield; 


96 

that  conflict,  which  began  by  both  armies  assuming  the 
aggressive,  terminated  by  each  being  so  strongly  in- 
trenched that  the  other  did  not  consider  it  prndent  ta 
continue  the  attack. 

95.  In  the  face  of  an  active  defense,  muhiplying  its 
counter  attacks  and  offensive  returns,  tlie  attack  will 
have  great  difficulty  in  maintaining  itself  in  the  conquered 
positions  where  it  will  nearly  always,  immediately  after 
the  capture,  be  compelled  to  take  up  the  defensive  atti- 
tude for  a  certain  length  of  time.  It  must  therefore  have 
recourse,  like  the  defense,  to  the  resources  of  fortifica- 
tion, in  preparing  the  boundaries  of  woods  and  villages, 
in  making  the  intrenchments  face  the  other  way,  or  in 
building  new  ones,  and  in  doing  these  things  as  rapidly 
as  possible. 

In  darkness  or  fog  an  advance  may  be  made  close  up 
to  the  defensive  line  and  a  good  intrenched  position 
taken  up.  . 

96.  The  location  of  the  fortifications  of  this  char- 
acter upon  the  battlefield  will  be  determined  by  the  posi- 
tion of  the  line.  Troops  in  contact  with  the  enemy  can 
not  remain  stationary  without  cover.  An  advance  can 
be  made  in  the  open,  utilizing  such  natural  cover  as  may 
exist  at  the  locality.  A  withdrawal  in  the  open  is  more 
difficult  than  the  advance;  and,  with  modern  weapons,  is 
more  destructive,  unless  the  attention  of  the  enemy  can 
be  retained  by  other  covering  bodies  of  troops.  To  re- 
main without  cover  in  the  open  is  annihilation.  An  ad- 
vancing force,  if  it  cannot  push  its  way  further,  must 
obtain  cover  where  it  is  or  go  back.  The  former  will  be 
less  costly,  and  if  the  line  cannot  be  reinforced,  it  will 
be  best  to  get  such  cover  as  it  can  manage  to  throw  up, 
and-liolcLon  until  dark.     What  is  called  the  skirmisher's 


97 

irejich,  .or.pit,  can  be  excavated  by  a  soldier  while  j.ving- 
down,  and  will  be  what  he  will  try  to  secure  after  having 
heaped^a ipound  of  earth^or  segured  any  other  cover  in 
front__af-hi&  heatUin_.the  most  expeditions  rnanner  pos- 
sible. (See  paragraph  9  and  figures  3  and  4,  E.  F.  M.) 
Similarly  a  line  that  is  being  pushed  slowly  back  will  en- 
deavor to  intrench  itself  at  the  first  opportunity,  and 
maintain  its  ground. 

97.  Such_trenches  or  cover  are  wholly  tactical ;  they 
cannot  be  prepared  in  advance,  for  they  depend  upon  the 
position  of  the  troops  and  must  conform  to  that  con.di- 
tion.  They  must  be  constructed  by  the  troops;  and  that 
one  of  the  opposing  forces,  which  has  its  officers  l^est 
able  to  advantageously  locate  the  trenches  within  the  lim- 
its allowed,  its  men  trained  to  realize  the  importance  of 
cover  and  provided  with  means  for  doing  the  work  in 
the  shortest  time,  will  have  a  great  advantage  over  an 
army  deficient  in  any  one  of  these  respects. 

Such  constructions  will  ordinarily  form_iiit^enohed 
lines  rather  than  fortified  positions,  although  the  latter 
may  be  developed  from  them. 

Major  Kuhn  states :  "In  their  attacks  on  the  Rus- 
sian positions,  the  Japanese  firing  lines,  lines  of  support^ 
and  reserves  frequently  constructed  hasty  intrenchmcnts 
as  they  advanced  over  the  fire  zone.  These  intrench- 
ments  were  of  the  simplest  form  to  give  cover  quickly, 
being  thrown  up  with  the  portable_intr£nching  tool  car- 
ried by  the  sokliers,  and  giving  cover  lying  down  or 
kneeling.  They  served  to  cover  the  successive  advances 
of  the  infantry  line,  being  occupied  m  turn  by  the  firing- 
line,  lines  oTsupport,  and  reserves,  and  being  continually 
strengthened  by  the  rearmost  lines." 


98 

Major  Morrison  states :  "Around  Liaoyang  hasty 
intrenchments  were  frequently  used  by  the  Japanese. 
Troops  pushed  forward  against  the  Russian  works,  when 
checked,  threw  up  hasty  cover,  sometimes  kneehng  or 
lying,  but  more  generally  merely  head  cover.  This  con- 
sisted simply  in  digging  and  throwing  the  dirt  to  the 
front,  height  and  thickness  depending  on  the  circum- 
stances of  the  case. 

"At  this  place  I  saw  cover  constructed  for  the  reserve. 
It  consisted  of  parallel  mounds  of  earth  thrown  up  about 
20  paces  apart  and  about  3  feet  high,  including  the  trench, 
behind  which  the  troops  could  sit.  I  was  told  it  was  ef- 
fective cover  for  shrapnel.  They  were  out  of  range  of 
infantry  fire. 

"In  the  advances  on  the  Sha  River  hasty  intrench- 
ments were  in  constant  use.  They  presented  no  new  fea- 
tures. 

"One  trench  constructed  by  the  Russians  and  cap- 
tured by  the  Japanese  was  converted  to  their  own_Lise 
by  the  latter  by  digging  a  trench  on  the  reverse  side. 

"As  far  as  I  could  observe  or  find  out  by  questioning, 
the  hasty  cover,  either  kneeling  or  standing,  was  safe 
cover  from  shrapnel  while  the  men  remained  close  be- 
hind it." 

General  Kuropatkin  in  his  "Study  of  Japanese  Tac- 
tics," states  :  "We  once  had  an  opportunity  of  closely 
watching  an  advance  made  by  the  Japanese  against  the 
front  of  the  position  held  by  the  Thirty-eighth  Alrofski 
Infantry  Regiment. 

"They  attacked  in  widely  extended  skirmishing  order. 
The  firing  line  advanced  at  the  double  for  a  short  dis- 
tance, lay  dowjvand  comrnenced  to  dig.  Notwithstand- 
ing our  extremely  heavy  fire,  they  again  doubled   for- 


99 

ward,  giving"  up  their  half  constructed  trenches,  and  be- 
gan to  dig  new  ones.  The  supports  then  doubled  for- 
ward and  occupied  the  first  trenches  and  completed  them. 
When  the  firing  line  advanced  from  the  second  line  of 
trenches,  these  were  occupied  by  the  supports,  and  the 
reserves  then  moved  up  into  the  first  line  of  trench.  The 
advance  continued  by  successive  rushes  in  this  manner." 
98.  Siege  Operations. — Any  field  army  may  be 
called  upon  to  attack  fortified  places,  and  such  operations 
may  include  all  the  refinements  of  regular  siege  opera- 
tions. (For  the  details  of  siege  operations  see  para- 
graphs 65-118,  E.  F.  M.) 


100 


CHAPTER  X. 

Calculation  of  Men  and  Time  Required  to 
Execute  Defensive  Works. 

99.  Tasks. — The  capacity  of  the  average  untrained 
man  for  continuous  cHgg-ing  does  not  much  exceed  80 
cubic  feet  for  easy  soil,  60  cubic  feet  for  medium,  and  40 
cubic  feet  for  hard  soil.  He  will  do  three-eights  of  this 
in  the  first  hour,  five-eights  in  the  first  two  hours,  and 
the  other  three-eights  in  the  other  two  hours.  In  addi- 
tion to  the  fact  that  he  works  but  a  little  over  half  as 
fast  in  the  second  two  hours,  four  hours'  work  will  leave 
him  unfit  for  fighting  or  marching,  while  after  two  hours' 
work  he  should  be  able  to  do  either.  The  quantity  of 
work  assigned  to  each  relief  should  be  that  which  can 
probably  be  done  in  two  hours,  and  the  relief  is  required 
to  finish  it  and  no  more,  whether  it  takes  less  or  more 
time.  For  the  first  work,  the  soil  is  apt  to  be  loose  and 
the  lift  less,  so  that  a  slightly  greater  task  should  be 
given  to  the  first  relief  than  to  the  second.  Assuming 
men  at  five  foot  intervals  and  neglecting  fractions,  the 
number  of  hour's  work  required  to  throw  up  a  parapet 
is  the  section  of  the  parapet  in  square  feet  divided  by 
five  for  eas}-,  four  for  medium,  and  two  and  one-half 
for  hard  soil. 

When  men  and  tools  are  plenty  and  it  is  desirable  to 
complete  the  work  promptly,  the  tasks  may  be  made 
four  feet  long,  but  at  night  five  foot  intervals  are  neces- 
sary to  prevent  interference  or  possible  injury  to  the  men. 
(See  E.  F.  M.,  paragraphs  37-43.) 

100.     Double  Gangs. — When  men  are  plenty,   tools 


101 

are  scarce,  or  time  presses,  a  task  may  be  completed  in 
about  two-thirds  of  the  ordinary  time  by  detaihng  two 
men  at  each  set  of  tools.  The  two  gangs  change  off  at 
frequent  intervals  and  the  men  work  as  rapidly  as  pos- 
sible. 

101.  Where  traction  ditchers  are  available,  as  in 
many  cities  and  towns,  they  may  often  be  advantageously 
used  to  construct  infantry  trenches.  Some  forms  can 
dig  a  ditch  thirty  inches  wide  and  three  feet  deep  at  the 
rate  of  one  yard  per  minuted 

102.  The  Fort  Riley  redout  (figure  205,  E.  F.  M.) 
for  one  battalion  could  be  constructed  by  its  garrison  in 
six  days  of  ten  hours.  If  plows  and  scrapers  were  used 
in  addition  to  the  men,  it  would  require  about  four  days. 
(See  paragraph  42.) 

103.  The  Russian  redout  (figure_l}  for  one  com- 
pany could  be  constructed  by  its  garrison  in  about  six 
hours  in  ordinary  soil.      (See  paragraph  42.) 

104.  The  Japanese  redout  (figure  2)  for  one  bat- 
talion could  be  constructed  by  its  garrison  in  two  days 
of  ten  hours.     (See  paragraph  42.) 

105.  The  profile  shown  in  figure  3  has  a  trench 
area  of  cross  section  of  6  square  feet,  and  applying  the 
approximate  rule  in  paragraph  99,  could  be  constructed 
in  from  one  to  two  hours.  The  profile  shown  in  figure 
4  with  a  trench  area  of  9  square  feet  would  require  from 
two  to  three  hours.     (See  paragraph  45.) 

106.  The  triangular  profile  shown  in  figure  5  with 
a  parapet  area  of  22  square  feet  could  be  constructed  in 
from  two  to  four  hours  with  two  men  per  4  feet  of 
length.  The  triangular  profile  shown  in  figure  6,  with 
a  parapet  area  of  44  square  feet,  could  be  constructed 


102 

in  from  four  to  eight  hours,  and  would  require  three  men 
per  4  feet  of  length,  on  account  of  the  excessive  hori- 
zontal movement  of  earth  necessary.  For  the  additional 
men  necessary  for  the  construction  of  the  revetment,  see 
paragraph  117.  With  a  scraper  and  plow  20  to  30  feet 
of  parapet  could  be  constructed  per  day  of  eight  hours. 
(See  paragraph  45.) 

107.  The  Japanese  profile  shown  in  figure  7  has  a 
trench  area  of  20  square  feet  and  could  be  constructed 
in  from  four  to  eight  hours.  That  shown  in  figure  8  has 
a  trench  area  of  28  square  feet  and  could  be  constructed 
in  from  six  to  eleven  hours.  (See  paragraph  45.)  In 
both  these  profiles  two  men  per  5  feet  of  length  could  be 
worked  and  the  time  could  be  halved.  For  the  addi- 
tional men  necessary  for  the  construction  of  the  revet- 
ment, see  paragraph  117. 

108.  The  Russian  profile  shown  in  figure  9  has  a 
trench  area  of  18  square  feet  and  could  be  excavated  in 
from  four  to  eight  hours.  The  loopholes,  loophole  covers 
and  sand-bag  traverses  would  require  about  four  hours 
additional.  This  trench  was  actually  constructed  in  two 
nights.     (See  paragraph  45.) 

109.  The  profile  shown  in  figure  10  has  a  trench 
area  of  16.5  square  feet  and  could  be  excavated  in  from 
four  to  eight  hours.  The  construction  of  the  splinter- 
proof  would  require  an  extra  man  per  5  foot  task.  (See 
paragraphs  46  and  49.) 

110.  The  loophole  cover,  figure  11.  could  be  con- 
structed in  half  an  hour  by  one  man  if  the  materials  were 
convenient.     (See  paragraph  46.) 

111.  The  earthwork  of  the  ])rofile  sliown  in  figure 
12  could  be  executed  in  from  two  to  three  liours.     The 


103 

loojjholes  and  overhead  cover  would  require  two  hours 
additional.     (See  paragraph  49.) 

112.  The  splinter-proofs  shown  in  figures  13  and  14 
would  require  from  one  to  two  hours  for  construction 
with  two  men  per  5-foot  task,  if  the  materials  were  at 
hand.     ( See  paragraph  49. ) 

113.  The  communicating  trench,  figure  17,  has  an 
area  of  12  square  feet  and  could  be  constructed  in  from 
two  to  four  hours.  With  a  width  of  2  feet  it  would 
have  an  area  of  8  square  feet  and  would  require  from 
one  and  one-half  to  three  hours.      (See  paragraph  55.) 

114.  The  gun  pit,  figure  18,  has  a  total  volume  of 
excavation  of  330  cubic  feet  and  could  be  constructed  by 
twelve  men  in  from  one  to  two  hours.  (See  paragraph 
67.) 

115.  The  Russian  observing  station,  figure  21,  could 
be  constructed  by  ten  men  in  eight  hours.  (See  para- 
graph 71.) 

116.  The  emplacement  for  two  machine  guns,  figure 
22,  has  a  total  volume  of  excavation  of  340  cubic  feet  and 
could  be  constructed  by  eight  men  in  from  one  and  one- 
half  to  four  hours.     (See  paragraph  73.) 


104 


117.     The   following  table   gives  the  time   required 
to  execute  different  kinds  of  work  in  hours  of  one  man: 


Description  of  Work. 

Figure  in  En- 
gineer Field 
Manual, Parts 

Work  done  by  one 
man  in  one  hour 

Remarks. 

Cutting  brushwood 

6  years  old. 

15  sq.  yds. 

Cutting  only. 

Felling  trees  with  axe, 

untrained  men  : 

' 

4  in.  diameter   .  .  . 

No.  30 

10 

6 

3 
2 
0.6 

6  in.  diameter   .  .  . 

9  in.  diameter.  .  .  . 

2  men  to  each 
'     tree. 

12  in.  diameter.  .  .  . 

1 8  in.  diameter.  .  .  . 

30  in.  diameter.  .  .  . 

Abatis,  small  trees  close 

^ 

at  hand,  10  yds.  wide 

90 

0.25  yd. 

Slashing,  10  yds.  wide . 

Ql 

I       yd. 

At  edge  of 

Low   wire   entangle- 

woods, etc. 

ment,   10  yds.  wide.  . 

I        yd. 

High  wire  entangle- 

ment, 10  yds.  wide.  .  . 

lOI 

0.3      yd. 

Military  pits,  5  rows. 

104 

0.5     yd. 

Walls,  loopholes  cut 

with  chisels 

log 

No.    4 

I  man  to  each. 

Walls,  notches  at  top 

loS 

No.  20 

I  man  to  each. 

Gabions  

64 

No.    0.3 

3  men  to  each. 

Fascines,  18  ft. 

55 

No.    0.2 

5  men  to  each. 

Hurdles,  6  ft.  by  2  ft. 

9  in 

61 

No.    0. 2 

3  men 

Sand  bag  revetment.  .  . 

53 

8.8  sq.  ft. 

5  men 

Sod  revetment 

54 

5     sq.  ft. 

Continuous   hurdle 

revetment 

2     sq.  yds 

Gabion  revetment 

65 
59 
34 

Executed  at 

Fascine  revetment.  .  . 

same  time  as 

Overhead  cover 

Siege  gun   emplace- 

4    sq.  ft. 

earthwork. 

Not  including 
earthwork. 

ment  

118 

0.005 

70  men,  10  hrs. 

105 


CHAPTER  XI. 
Field  Problems  in  Fortification. 

118.  Field  Problems  in  Fortification  are  intended  to 
take  up  the  details  of  the  phase  of  terrain  exercises,  such 
as  are  given  in  the  Military  Art  Department,  following 
the  issuing  of  the  order  for  taking  up  a  defensive  posi- 
tion. 

119.  The  course  in  Field  Problems  in  Fortification 
for  the  Staff  Class  consisted  of  eight  problems  for 
which  34  half-days  were  employed. 

In  the  first  five  problems  the  force  involved  was  a 
detachment  consisting  of  a  regiment  of  infantry,  a  bat- 
tery of  field  artillery  and  sometimes  a  troop  or  more  of 
cavalry.  The  problems  were  varied  by  placing  them  on 
different  kinds  of  terrain,  by  varying  the  time  available 
for  the  preparation  of  the  position,  and  by  variations  in 
the  probable  direction,  nature,  and  strength  of  the  ex- 
pected attack.  For  problems  involving  a  force  of  this 
size  three  half-days  were  employed. 

On  the  first  half-day  a  general  examination  of  the 
terrain  was  required,  with  a  statement  of  the  general 
position  to  be  occupied ;  division  into  sectors,  and  force 
assigned  each;  position  and  strength  of  the  reserve;  the 
position  of  the  artillery,  kind  of  fire  to  be  employed  and 
shelter  to  be  constructed ;  disposition  and  use  of  the 
cavalry. 

On  the  second  half -day  a  more  detailed  examination 
of  the  terrain  was  required,  with  division  of  the  force 
into  first  line  and  supports ;  location  and  design  of  the 
infantry  works  and  garrison  of  each;  position  and  shelter 


106 

for  supports;  communications  and  approaches  to  be  con- 
structed; obstacles;  clearing  of  the  foreground;  and 
demolitions  to  be  executed. 

On  the  third  half-day  the  problem  was  discussed  on 
the  ground.  During  the  discussion  the  instructor  read 
a  summary  of  the  various  solutions,  and  required  different 
ofiBcers  to  explain  any  unusual  dispositions,  inviting  a 
free  discussion  of  all  the  points  involved.  Details  were 
then  made  to  trace  the  various  trenches  and  positions. 
The  locations  were  discussed  by  the  whole  class,  and 
the  best  location  at  each  point  decided  upon.  When  the 
time  permitted,  the  whole  line  was  traced  on  the  ground 
simultaneously,  by  assigning  officers  as  commanders  of 
the  various  units  and  requiring  them  to  issue  their  orders 
and  trace  the  trenches  of  their  commands.  Each  officer 
was  provided  with  a  sharpened  stake  about  three  feet 
long  to  which  was  attached  25  yards  of  tracing  tape  or 
cord.  With  these  stakes  the  actual  length  of  the  trenches 
to  be  constructed  could  be  traced  on  the  ground  by  assign- 
ing the  proper  number  of  officers  at  each  trench.  In  this 
way  the  officers  can  get  a  proper  idea  of  the  amount  of 
ground  covered  by  the  trench  of  any  unit. 

After  a  discussion  of  the  problem  an  approved  solu- 
tion was  issued  by  the  department. 

The  sixth  problem  involved  a  force  of  a  detached 
brigade  consisting  of  three  regiments  of  infantry,  a 
squadron  of  cavalry,  a  battalion  of  field  artillery,  a  com- 
pany of  engineers,  a  company  of  signal  corps,  and  a 
field  hospital.  For  this  problem  five  half-days  were  em- 
ployed. 

On  the  first  half-day  the  following  requirements  were 
solved:  General  position  to  be  taken  up;  the  division 
into  sectors,  and  the  force  asigned  each ;  the  position  and 


107 

stren"-th  of  the  reserve ;  the  location  of  the  field  artillery, 
character  of  the  protection  to  be  provided,  and  kind  of 
fire  to  be  used ;  disposition  and  use  of  the  cavalry ;  duties 
to  be  assigned  the  engineer  and  signal  companies;  loca- 
tion of  the  field  hospital,  ambulance  and  dressing  stations. 
On  the  second  half-day  the  first  sector  was  taken  up 
in  detail  in  the  same  manner  as  in  the  smaller  problems. 
The  third  half-day  was  devoted  to  a  discussion  of  the 
previous  work. 

On  the  fourth  half -day  the  dispositions  of  the  second 
sector  were  required ;  and  were  discussed  on  the  fifth 
half -day. 

The  seventh  problem  involved  the  dispositions  and 
defensive  works  of  a  division  with  siege  artillery,  which 
was  part  of  a  force  of  a  corps  of  three  divisions  required 
to  take  up  and  hold,  for  about  a  month,  a  strong  position 
covering  the  bridges  across  the  Missouri  at  Leavenworth 
and  Fort  Leavenworth,  assuming  about  ten  days  were 
available  for  the  preparation  of  the  position. 

Ten  half-days  were  allowed  for  the  solution  and  dis- 
cussion of  this  problem,  which  was  taken  up  first  in  gen- 
eral and  then  in  detail  as  in  the  sixth  problem. 

The  eighth  problem  involved  an  attack  of  a  brigade, 
with  siege  and  field  artillery,  an  engineer  battalion,  signal 
company  and  field  hospital,  by  regular  siege  methods,  on 
a  part  of  the  line  prepared  for  defense  in  the  seventh 
problem;  under  the  assumption  that  the  position  had  been 
invested  by  a  force  of  two  corps  with  a  siege  train.  Four 
half-days  were  devoted  to  this  problem. 

On  the  first  half-day  were  required:  The  location 
of  the  brigade  park;  the  location  of  the  siege  artillery, 
character  of  the  emplacements,   observing   stations;  the 


108 

location  of  the  field  artillery,  character  of  the  protection 
to  be  provided. 

On  the  second  half-day :  Location  and  construction 
of  the  first  parallel ;  and  the  approaches  to  the  front  and 
rear. 

On  the  third  half-day :  Location  and  construction  of 
the  second  and  third  parallels  and  approaches;  duties 
assigned  the  engineer  battalion  and  signal  company ;  loca- 
tion of  field  hospital,  ambulance  and  dressing  stations. 

The  fourth  half-day  was  devoted  to  a  discussion  of 
the  problem,  and  laying  out  the  parallels  and  approaches. 

120.  The  chief  value  of  these  problems  is  their  solu- 
tion on  the  terrain  itself,  and  the  actual  laying  out  of 
the  works  on  the  ground.  The  map  is  only  used  to 
enable  the  instructor  to  determine  the  dispositions  of  each 
officer  and  to  have  a  record  of  the  work  done  by  each. 

121.  The  following  general  instructions  were  issued 
the  Staff  Class  for  the  course : 

( 1 )  Each  officer  will  be  equipped  with  a  pad  5x8 
inches,  pencil,  pocket  knife,  field  glass,  scale  of  yards 
3  inches  to  1  mile,  scale  of  slopes,  "Applied  Principles 
of  Field  Fortification,"  and  Part  V,  Engineer  Field 
Manual. 

(2)  A  map  for  each  problem,  scale  3  inches  to  1 
mile,  will  be  issued. 

(3)  On  the  half-days  scheduled  for  the  discussion 
of  problems,  each  officer  will  be  issued  tracing  tape  and 
stakes  for  locating  trenches  on  the  ground. 

(4)  In  the  field  problems  all  decisions  and  locations 
will  be  made  after  a  careful  examination  of  the  ground. 
The  map  is  issued  only  for  purposes  of  identification  and 


109 

record,  and  all  works  will  be  clearly  and  accurately  indi- 
cated on  it  to  scale. 

(5)  The  solution  of  the  problem  will  include  any 
necessary  explanation  of  the  notations  made  on  the  map ; 
brief  reasons  for  decisions  made  or  work  to  be  executed ; 
drawings  of  profiles  and  sections  of  work  not  in  the  man- 
uals issued;  estimates  of  time  and  force  required  to 
execute  each  part  of  the  work;  order  in  which  each  part 
is  to  be  undertaken ;  methods  to  be  used ;  tools  and  ma- 
terial necessary;  arrangement  of  working  parties,  and 
total  time  to  be  devoted  to  the  preparation  of  the  position. 

122.  After  several  problems  of  the  same  type  have 
been  worked  out  in  detail  as  above  described,  so  that  the 
student  officers  understand  the  amount  and  kind  of  work 
that  can  be  done  in  a  given  time,  the  class  may  be  given 
a  situation  and  required  to  trace  the  trenches,  approaches, 
points  of  support,  and  positions  of  supports,  reserves, 
artillery,  etc.,  in  the  time  that  it  would  have  to  be  done 
in  actual  service.  Officers  may  be  assigned  to  commands, 
and  required  to  issue  their  orders,  with  and  without  maps 
of  the  terrain. 

When  the  entire  position  has  been  traced  upon  the 
ground,  the  class  should  go  over  it  and  discuss  the 
various  locations. 

123.  The  following  problems  selected  from  those 
given  the  Staff  Class  are  given  as  examples  of  the  simpler 
ones  in  the  course.  A  solution  of  each  problem  is  also 
given  with  the  dispositions  indicated  on  the  map.  It 
must  be  understood  that  these  are  in  no  sense  map  prob- 
lems, but  are  solved  on  the  actual  terrain,  and  that  they 
are  indicated  on  the  map  only  to  give  an  idea  of  the  dis- 
positions made  on  the  ground. 


110 

The  maps  are  all  of  a  scale  of  three  inches  to  one 
mile,  too  small  a  scale  to  indicate  the  dispositions  accu- 
rately. 

124.  In  order  to  obtain  the  most  benefit  from  these 
problems,  it  is  recommended  that  the  student  make  his 
own  solutions  on  the  map,  before  reading  the  solutions 
given.  The  map  of  Fort  Leavenworth  and  Vicinity,  scale 
4  inches  to  1  mile,  is  best  suited  for  this  purpose,  and 
can  be  obtained  from  the  Secretary  of  the  Army  Service 
Schools. 


Ill 


FIELD  PROBLEM  NUMBER  ONE. 

General  Situation : 

A  Red  battalion  which  was  sent  from  Platte  City, 
Mo.,  (12  miles  east  of  the  Taylor  S.  H.)  to  capture  sup- 
plies collected  at  Lowemont,  Kan.,  (6  miles  west  of  the 
Taylor  S.  H.)  having  encountered  a  superior  Blue  force 
at  the  latter  place,  has  retired  via  the  Millwood  road. 
Special  Situation — Blue  : 

The  Blue  pursuing  force:  1st  Infantry;  Battery  E, 
3d  Field  Artillery;  and  Troop  C,  5th  Cavalry,  is  under 
command  of  Colonel  A,  who  has  orders  to  drive  the 
Red  force  east  of  the  Missouri  River,  and  seize  the  Fort 
Leavenworth  bridge. 

The  remainder  of  the  Blue  force  (2d  and  3d  Infan- 
try) which  was  delayed  at  Lowemont,  cannot  reach  the 
Taylor  S.  H.  before  3  p.  m.,  September  23,  1908. 

At  10  A.  M..  when  Colonel  A  at  the  head  of  the  main 
body  arrives  at  Taylor  S.  H.,  he  receives  a  captured  mes- 
sage stating  that  five  battalions  of  infantry  and  one  bat- 
tery of  field  artiller}^  are  on  their  way  to  reinforce  the 
Red  battalion,  and  expect  to  reach  986  at  noon. 

The  cavalry  reports  that  the  Red  battalion  has  de- 
ployed on  the  edge  of  the  woods  near  Kern,  leaving  a 
small  force  near  854. 

Colonel  A  decides  to  take  up  a  position  and  to  pre- 
pare it  for  defense,  in  order  to  hold  back  the  enemy  until 
the  arrival  of  the  remainder  of  the  Blue  force. 

The  Leavenworth  bridge  has  been  destroyed. 

Required : 


112 

First  Part. 

1.  The  general  position  to  be  taken  up. 

2.  Division  into  sectors,  and  force  assigned  each. 

3.  The  position  and  strength  of  the  reserve. 

4.  The  position  of  the  artillery,  kind  of  fire  to  be 
employed  and  shelter  to  be  constructed. 

5.  The  disposition  and  use  of  the  cavalry. 

Second  Part. 

6.  For  each  sector  : 

(a)  The  division  into  first  line  and  supports. 

(b)  Location  and  design  of  infantry  works  and 
garrison  of  each. 

(c)  Position  and  shelter  for  supports. 

(d)  Communications  and  approaches  to  be  con- 
structed. 

(e)  Obstacles  to  be  constructed. 

(f)  Clearing  of  the  foreground. 

(g)  Demolitions  to  be  executed. 

Third  Part. 
Discussion  of  the  problem  on  the  ground. 

SOLUTION FIELD   PROBLEM    NO.    1. 

First  Part. 

1.  Hill  883— hill  875— hill  862,  overlooking  Salt 
Creek.  This  position  has  a  clear  field  of  from  400  to  600 
3'-ards  west  of  Salt  Creek,  a  strong-  obstacle  in  its  front, 
and  its  flanks  are  well  protected.  Salt  Creek  is  about 
fifty  feet  wide,  with  two  to  four  feet  of  water,  a  very 
soft  bottom,  and  vertical  banks  ten  to  fifteen  feet  high. 


113 

The  extreme  front  is  1,500  yards,  but  the  main  position, 
excluding  hill  862  and  the  positions  of  the  supports,  is 
900  yards  long.  The  working  parties  will  be  under  long 
range  infantry  fire  (1,600  yards)  of  the  enemy  at  the 
edge  of  the  woods  east  of  Kern,  but  can  be  protected  by 
a  force  thrown  out  to  the  front  near  Sharp. 

An  alternative  position  is  that  along  the  ridge  932 — 
886,  which  has  the  advantage  of  being  out  of  range  of 
the  enemy,  but  would  give  up  the  obstacle  of  Salt  Creek 
and  the  ground  to  the  west,  and  would  make  a  kiter 
advance  all  the  more  difficult.  It  has  practically  no  bet- 
ter field  of  fire  and  has  no  strong  positions  for  the  flanks; 
see  pars.  7-18  and  78-85. 

2.  Right  sector :  Kickapoo — Leavenworth  road  in- 
clusive to  Millwood  road  exclusive.  Left  sector:  Mill- 
wood road  to  hill  862,  both  inclusive.  One  battalion  is 
assigned  to  each  sector;  the  machine  gun  platoon  to  the 
left  sector ;  see  pars.  22,  23  and  38. 

3.  At  865.  one  battalion.  This  is  a  central  location, 
well  covered  by  the  road  cut,  and  is  near  tlie  more 
exposed  right  flank;  see  pars.  26  and  84. 

4.  At  hill  886.  Lidirect  fire  will  be  used  at  first ;  i  f 
necessary,  direct  fire  will  be  used  to  reach  the  attacking 
infantry.  No  artificial  cover  will  be  constructed.  This 
position  is  well  protected  from  the  hostile  artillery  which 
would  probably  be  posted  on  Hancock  Hill.  It  covers  the 
edge  of  the  woods  east  of  Kern  at  a  range  of  3,200  yards, 
enfilades  the  ravines  on  each  flank  of  the  main  infantry 
line  and  is  well  separated  from  the  infantry  positions ; 
see  pars.  15,  30-34,  65,  67  and  68. 

5.  The  cavalry  will  be  ordered  to  keep  t(iuch  with 
the  eneni}-;  and  when  driven  in,  cover  the  right  flank, 
sending  a  squad  to  the  left. 


lU 

Second  Part. 

6.  (a)  For  each  sector:  Three  companies  in  the 
first  line;  no  local  supports;  sector  support,  one  company. 
Local  or  company  supports  will  not  be  employed,  as  the 
reverse  slopes  are  too  gentle  to  afford  cover  from  artil- 
lery fire  ;  the  firing  trenches  will  probably  not  be  subjected 
to  much  artillery  fire ;  there  are  no  good  covered  ap- 
proaches to  the  firing  line,  and  the  enemy's  attack  is  likely 
to  develop  suddenly  from  Salt  Creek;  see  pars.  23,  78, 
79  and  82. 

(b)  See  map.  Trenches  are  constructed  for  eight 
companies,  120  yards  per  company;  total  lengtli,  960 
yards.  With  tasks  of  five  feet  per  man,  this  will  require 
3/5X960=576  men. 

Profile :  Standing  trench,  see  figure  3.  This  has  an 
area  of  cross  section  of  6  square  feet.  The  soil  is  clay 
and  may  be  classed  as  medium.  6^4=  1|^  hours  required 
to  complete  the  trench;  see  pars.  99  and  105.  No  con- 
cealment, loopholes,  nor  dummy  trenches,  as  work  will 
have  to  be  done  in  view  of  the  enemy,  and  the  time  is 
limited.  Trench  for  H  company  will  be  concealed  by 
the  standing  corn.  The  profile  adopted  with  its  low  and 
flat  parapet  is  very  inconspicuous;  see  pars.  45  and  63. 

Machine  gun  emplacement  constructed  by  platoon  in 
two  hours,  with  sand  bag  loopholes,  covering  the  Mill- 
wood road;  see  pars.  73  and  116,  and  figure  22.  Sand 
bags  will  be  stored  in  trench  so  that  the  guns  may  be 
raised  to  fire  over  crest  of  parapet,  if  wider  field  of  fire 
becomes  necessary.  . 

Tools  required  :  Those  carried  by  the  men  and  in 
the  wagons,  including  those  of  the  reserve.     See  appen- 


115 

dix.  Practically  no  tools  can  be  obtained  from  the 
neighboring  farms.  Work  will  be  done  in  one  relief, 
seventy-two  men  in  each  company  with  sho\'els,  twenty 
with  picks. 

(c)  See  map.  G  Company  will  scar]:)  the  reverse 
slope  and  throw  the  earth  to  the  front  so  as  to  give  cover 
for  men  sitting,  for  a  length  of  fifty  yards.  Tliis  re- 
Cjuires  3/5X50=30  men,  4  hour,  and  will  be  done  when 
the  company  completes  its  firing  trench.  A  company  is 
protected  by  a  retired  firing  trench  as  shown  on  map; 
see  par.  56. 

(d)  None,  on  account  of  lack  of  time,  men,  and 
tools;  see  pars.  55  and  75. 

(e)  None  except  those  involved  in  f ;  see  par.  59. 

(f)  Standing  corn  in  front  of  E  and  H  Companies 
broken  down  parallel  to  the  front  by  dragging  a  log  over 
it  with  a  team.  Trees  and  brush  along  the  west  side  of 
Salt  Creek  slashed ;  see  par.  60.  For  this  work  there 
are  detailed  105—92=13  men  from  each  of  the  eight 
companies,  for  l-i-  hours,  with  the  axes  and  hatchets 
carried  by  the  companies ;  see  appendix. 

(g)  The  Daniels  houses  in  front  of  E  and  G  Com- 
panies will  be  burned.  The  bridge  at  789  should  not 
be  destroyed,  as  it  would  be  needed  for  a  future  advance 
of  the  detachment;  see  par.  61. 

The  work  to  be  carried  on  simultaneously  except  the 
support  position  for  G  Company.  The  men  will  be 
worked  1^  hours  in  one  relief.  Total  time  to  complete 
the  preparation  of  the  position,  two  hours. 

The  3d  Battalion  detailed  for  the  reserve  is  assumed 


116 

to  have  been  in  the  advance  guard.  It  will  keep  down 
the  fire  of  the  enemy  while  the  trenches  are  being-  con- 
structed, by  crossing  Salt  Creek  and  occupying  the  hill 
west  of  854.  When  the  work  is  completed  it  will  fall 
back  to  its  position  at  865. 


Field  Problem  N^l 


Se»U  3Inchc5-lMil. 


117 


FIELD  PROBLEM  NUMBER  TWO. 

General  Situation : 

A  Blue  division  is  retreating  through  Leavenworth 
towards  Atchison  (18  miles  northwest)  pursued  by  a 
Red  division. 

Special  Situation — Blue  : 

The  Blue  rear  guard  consisting  of:  2d  Infantry; 
Battery  B,  3d  Field  Artillery ;  Troops  C  and  D,  7th  Cav- 
alry, has,  on  September  14th  halted  for  the  night  near 
the  Taylor  house  on  the  Leavenworth-Kickapoo  road.  At 
6  P.  M.  the  rear  guard  commander  receives  orders  to  hold 
the  ground  south  of  Plum  Creek  until  noon  September 
15th.  Information  is  received  that  the  immediate  pur- 
suing force  of  th-e  enemy  consists  of  about  4,000  me'i 
of  all  arms,  and  is  camped  in  Leavenworth,  with  out- 
posts on  the  ridge  west  of  town. 

The  rear  guard  commander  decides  to  take  up  a 
defensive  position  and  to  fortify  it  as  strongly  as  the 
time  permits. 

Required : 

First  Fart. 

1.  The  general  position  to  be  taken  up. 

2.  Division  into  sectors,  and  force  assigned  each. 

3.  The  position  and  strength  of  the  resen^e. 

4.  The  position  of  the  artillery,  kind  of  fire  to  be 
employed,  and  shelter  to  be  constructed. 

5.  The  disposition  and  use  of  the  cavalry. 


118 

Second  Part. 

6.     For  each  sector : 

(a)  The  division  into  first  hue  and  supports. 

(b)  Location  and  design  of  infantry  works  awd 
garrison  of  each. 

(c)  Position  and  sheker  of  supports. 

(d)  Communications  and  approaches  to  be  con- 
structed. 

(e)  Obstacles  to  be  constructed. 

(f)  Clearing  of  the  foreground. 

(g)  Demolitions  to  be  executed. 

Third  Part. 
Discussion  of  the  problem  on  the  ground. 

SOLUTION FIELD   PROBLEM    NO.    2. 

First  Part. 

1.  The  main  line  of  defense:  Along  the  J-  Aaron 
ridge  from  road  874 — 812  to  include  hill  862.  An  ad- 
vanced line  from  the  Sprong  house— liill  883 — hill  875 
w^ill  also  be  held.  The  main  line  lias  a  length  of  1,800 
yards;  it  has  a  good  field  of  fire  of  about  800  yards;  its 
left  flank  is  strong,  the  right  is  rather  weak,  but  can  l)e 
covered  by  the  artillery  and  cavalry ;  the  reverse  slope  is 
steep  and  offers  good  cover  for  the  reserve;  the  hedges 
and  barbed  wire  fences  in  froiit  afford  good  olDstacles. 
In  order  to  give  more  depth  to  the  position  and  delay  the 
enemy,  the  advanced  line  is  occupied  by  part  of  the  force; 
see  par.  8.  This  position  has  a  front  of  about  1.700 
yards  and  a  good  field  of  fire  of  about  500  yards;  its 


110 

flanks  are  weak,  and  tlie  re\-erse  slopes  are  too  gentle  to 
afford  cover  for  supports  and  reserves  from  artillery  fire; 
it  is  therefore  not  suitable  for  the  main  position.  In 
this  problem  the  ground  south  of  Plum  Creek  has  to  be 
held  for  five  or  six  hours,  and  this  can  best  be  done  by 
causing  the  enemy  to  deploy  before  the  advanced  position, 
the  defenders  of  which  can  retire  by  the  ravines  in  rear 
without  masking  the  fire  from  the  main  line ;  see  pars. 
7-18  and  78-85.     ' 

2.  Right  sector:  from  the  road  S7A — 812  to  the 
Leavenworth-Kickapoo  road  inclusive.  Left  sector : 
from  the  Leavenworth-Kickapoo  road  exclusive  to  hill 
862  inclusive.  One  battalion  is  assigned  to  each  sector, 
the  machine  gun  platoon  to  the  left ;  see  pars.  22,  23 
and  38. 

3.  At  80'3,  one  battalion.  This  is  a  central  position 
well  covered  by  the  steep  slope;  see  pars.  26  and  84. 

4.  At  hill  849.  Indirect  fire  will  be  used.  No  arti- 
ficial cover  will  be  constructed.  This  position  covers  the 
exposed  right  flank  of  each  line  and  enfilades  the  ravines 
and  railroad  along  which  the  main  attack  of  the  enemy 
is  likely  to  be  made.  It  is  well  separated  from  the  in- 
fantry positions,  especially  the  position  of  the  reserve. 
It  would  be  very  difficult  for  the  enemy's  artillerv,  which 
is  probably  superior,  to  find  this  position;  and  it  is  about 
4,000  yards  from  Sentinel  Hill  and  Bell  Point  near  which 
the  enemy's  artillery  would  probably  be  located ;  see  ])ars. 
15,  30-34,  65,  67  and  68.  Crook  Point  affords  a  good 
observing  station. 

5.  To  reconnoiter  to  the  front  at  daylight  on  Sep- 
tember   15th,    gain   contact    with    the    enemv,    delav   his 


120 

advance,  and  cover   the  right  tlank.  sending  a  platoon 
to  the  left.     To  execute  the  demohtions  given  in  6  g. 

S^ecoiid  Fart. 

6.  (a)  For  each  sector:  Two  companies  in 
trenches  in  the  main  hne,  and  two  in  the  advanced  hne ; 
see  pars.  23,  78,  79  and  82. 

(b)  See  map.  Trenches  for  12  companies,  120 
yards  per  company,  total  length,  1,440  yards.  This  re- 
quires 3/5X1440=864  men,  or  72  men  per  company. 
Profile,  standing  trench,  see  figure  3.  Area  of  cross 
section  6  square  feet;  6^4=  H  hours,  add  4  hour  for 
night  work;  gives  total  time  2  hours.  Trenches  will  be 
concealed  with  grass  in  places  where  it  is  growing,  by 
corn  in  the  corn  fields,  and  by  top  soil  in  plowed  ground. 
No  loopholes  will  be  constructed  on  account  of  lack  of 
time  and  materials.  Dummy  parapets  shown  on  the  map 
will  be  constructed  by  plowing  two  or  more  furrows;  see 
pars.  45,  63  and  64. 

Machine  gun  emplacement  constructed  by  platoon  in 
two  hours  with  sand  bag  loopholes;  see  pars.  73  and  116, 
and  figure  22.  A  wide  field  of  fire  will  probable  be  neces- 
sary; this  can  be  secured  as  explained  in  Problem  No.  1. 

Tools  required :  Those  carried  by  the  men  and  in  the 
wagons  (see  appendix)  ;  as  there  are  not  sufficient  for  all 
the  men  working  at  once,  the  work  will  be  clone  in  two 
2-hour  reliefs.  492  men  in  each,  including  the  work  under 
d.  Six  teams  and  plows  will  be  requisitioned  from  the 
,  neighboring  farms  to  assist  in  the  construction  of  the 
trenches,  and  to  make  the  dummy  parapets.  The  reserve 
will  assist  in  the  construction  of  the  trenches  in  the  main 
line. 


FltLP  PboblemN»2 


I 


121 

(c)  No  supports  proper  will  be  used;  the  four  com- 
panies in  the  main  line  will  act  as  such  for  the  four  com- 
panies in  the  advanced  line;  see  par.  56. 

(d)  See  map.  For  profile  see  pars.  55  and  113  and 
figure  17,  2  feet  wide.  Total  length,  200  yards.  Re- 
quires 3/5X200=120  men,  2  hours,  or  30  men  from  each 
of  the  four  companies  on  the  advanced  line.  These 
approaches  will  enable  the  defenders  of  the  advanced 
line  to  retire  gradually  under  cover  when  the  enemy's 
attack  has  sufficiently  developed. 

(e)  None  except  those  involved  in  f ;  see  par.  59. 

(f)  Standing  corn  in  front  of  trenches  broken 
down  parallel  to  the  front  by  dragging  logs  over  it  with 
teams ;  see  par.  60. 

(g)  The  steel  bridges  over  Salt  Creek  at  French- 
man's, at  789  on  the  Millwood  road,  and  the  railroad 
bridg-e  at  the  mouth  of  Salt  Creek  will  be  disabled  by 
explosives  by  the  cavalry.  Requires  five  pounds  of 
dynamite  per  bridge,  placed  at  the  panel  point  of  each 
truss,  resting  on  the  abutment;  see  par.  128.  E.  F.  M. 
The  railroad  trestle  at  Miocene  will  be  burned.  Work 
will  be  done  by  patrols,  four  men  to  each  bridge,  after 
the  cavalry  has  been  forced  behind  Salt  Creek.  For 
tools  and  explosives  carried  by  the  cavalry,  see  appendix. 

.Total  time  to  prepare  position,  four  hours.  No  man 
will  work  more  than  two  hours.  The  work  should  be 
commenced  by  7  p.  m.  and  finished  by  11  p.  m.  by  moon- 
light. 

All  work  except  that  in  6  g  carried  on  simultan- 
eously. 


122 


FIELD  PROBLEM  NUMBER  THREE. 

General  Situation : 

A  Blue  army  based  on  Kansas  City  is  operating  along 
the  Misouri  Pacific  R.  R.  against  a  Red  army,  based  on 
Omaha.  Li  order  to  protect  its  line  of  communications 
against  cavalry  raids  of  the  enemy,  the  Blue  army  has 
fortified  various  points  along  the  railroad  in  its  rear. 

Special  Situation — Blue  : 

Colonel  A,  with  the  6th  Lifantry  and  Battery  C,  3d 
Field  Artillery,  has  been  ordered  to  fortify  Kickapoo, 
where  there  is  a  round-house,  repair  shops  and  materials 
for  the  repair  of  the  railroad.  It  is  not  believed  that  an 
attack  by  more  than  a  cavalry  brigade  with  artillery  is 
to  be  feared.  No  forces  of  the  enemy  are  reported  within 
sixty  miles  of  Kickapoo. 

Required : 

First  Part. 

1.  The  general  position  to  be  fortified. 

2.  Division  into  sectors  and  force  assigned  each. 

3.  The  position  and  strength  of  the  reserve. 

4.  The  position  of  the  artillery,  kind  of  fire  to  be 
employed  and  character  of  protection  to  be  constructed. 

5.  Interior  lines  of  defense. 

Second  Port. 

6.  For  each  sector : 

(a)  Division  into  first  line  and  supports. 

(b)  Location  and  design  of  infantry  works  in  the 
first  and  interior  lines. 


123 

(c)  Position  and  shelter  for  supports. 

(d)  Communications  and  approaches  to  be  con- 
structed. 

(e)  Obstacles  to  be  constructed. 

(f)  Clearing  of  the  foreground. 

(g)  Demolitions  to  be  executed. 

Third  Part. 
Discussion  of  the  problem  on  the  ground. 

SOLUTION FIELD  PROBLEM    NO.    3. 

First  Part. 

1.  Hill  1,000— 873— B.  Meyers— hill  903.  This  line 
is  3,000  yards  long — too  long  for  the  garrison  of  the 
town;  see  pars.  78-85;  but  it  is  necessar}^  to  hold  it,  as 
the  field  of  fire  on  the  left  would  be  too  restricted  if  the 
line  was  drawn  in  to  the  line  865 — hill  923.  The  field  of 
fire  on  the  right  is  good  for  400-500  yards;  on  the  left 
for  900-1,000  yards.  Section  Lane  and  Plum  Creek  form 
good  obstacles  on  the  left.  The  low  ground  along  the 
Missouri  River  is  intersected  by  numerous  sloughs  and 
is  too  marshy  and  wooded  for  an  attack  from  the  east ; 
see  pars.  87-90. 

2.  Right  sector :  North  and  west  of  the  line  842 — 
865 — 38.  Left  sector :  South  and  east  of  the  same  line. 
One  battalion  is  assigned  to  each ;  see  pars.  22  and  23. 

3.  At  38 ;  one  battalion  and  machine  gun  platoon ; 
see  pars.  26  and  38. 

4.  In  the  ravine  northwest  of  hill  923.  Indirect  fire 
will  be  employed  with  cover  of  the  type  shown  in  figure 
20.     Other  positions  will  be  selected  for  indirect  fire  so 


124 

that  all  the  slopes  in  front  of  the  position  may  be  swept 
by  fire.  Observing  stations  will  be  located  on  hills  1000, 
903  and  923.  The  probable  positions  of  the  enemy's  ar- 
tillery are  Crook  Point  and  hill  1042;  see  pars.  15,  27,  32, 
35,  65,  67,  and  68. 

5.  No  interior  line  for  right  sector;  for  left,  line 
865 — hill  923.  The  front  line  is  so  long  that  it  may  be 
necessary,  if  an  energetic  attack  is  made,  to  draw  in  the 
left,  giving  a  line  about  1,500  yards  long;  see  pars.  8. 
9,  and  19. 

Second  Part. 

6.  (a)  For  each  sector  Three  companies  in  the 
first  line,  each  with  one  section  in  firing  trenches  and 
three  in  local  support;  sector  support,  one  company;  see 
pars.  23,  78,  79  and  82. 

(b)  Location  shown  on  map.  Trenches  for  ten 
companies  in  the  first  line  (9  company  trenches  and  two 
platoon  trenches)  ;  and  for  four  companies  in  the  second; 
120  yards  per  company;  total  length  1,680  yards.  Pro- 
file: Figure  4,  see  pars,  45  and  105.  The  soil  is  clay 
and  may  be  classed  as  medium.  To  construct  trenches 
will  require  3/5X1,680=1,008  men,  2|  hours.  Loop- 
holes will  be  constructed  of  sod,  sand  bags,  or  stove  pipe, 
materials  to  be  obtained  in  vicinity.  Trenches  will  be 
carefully  concealed  with  sod,  top  soil  or  brush;  see  pars. 
46  and  63. 

Splinter-proof  cover  will  be  provided  for  one  section 
in  each  company  trench,  of  type  shown  in  figure  14.  This 
will  require  |X  1,680=420  men,  2  hours;  see  pars.  49 
and   112. 

Machine  gun  emplacements  of  type  shown  in  figure 


125 

22,  with  the  addition  of  splinter-proof  cover  constructed 
by  platoon  in  four  days  at  hill  1,000,  hill  923.  hill  903, 
and  covering-  the  road  and  railroad  east  of  hill  1,000;  see 
map.     Splinter-proof  cover  of  type  shown  in  figure  12. 

(c)  Company  supports  shown  on  map  at  S.  The 
sector  supports  at  C  and  G.  Protected  by  scarping  re- 
verse slope,  ^  yard  per  man.  This  will  require  20O  men 
four  hours  to  construct.  Similar  shelter  will  be  con- 
structed for  the  reserve  by  100  men  in  four  hours;  see 
par.  56. 

(d)  Approaches  shown  on  map,  leading  to  the  more 
advanced  trenches,  where  no  natural  covered  approaches 
exist.  Total  length,  800  yards;  profile,  figure  17.  These 
will  require  480  men  three  hours  to  construct.  The  exist- 
ing lateral  communications  are  sufficient;  see  pars.  55, 
75  and  113. 

(e)  Slashing  in  the  wooded  ravines  leading  to  the 
position,  along  the  river  road,  and  where  orchards  and 
woods  are  cleared.  Section  Lane  hedges  prepared  as  an 
obstacle  by  clearing  out  to  improve  the  field  of  fire  and 
filling  the  road  cuts  with  the  debris.  See  f  for  estimate 
of  time. 

High  wire  entanglements,  five  yards  wide,  constructed 
in  front  of  trenches  where  no  hedges  or  slashings  have 
been  prepared.  Total  length,  2,000  yards ;  this  will 
require  600  men  four  hours  to  construct,  material  taken 
from  barbed  wire  fences  ;see  pars.  59  and  117. 

(f)  Woods  and  orchards  slashed  in  front  of 
trenches  to  at  least  600  yards.  The  houses  that  interfere 
with  the  field  of  fire  will  be  torn  down  and  the  material 
used  for  splinter-proofs,  etc.  This  will  require  the  labor 
of  400  men  four  hours ;  see  pars.  60  and  117. 


126 

(g)      None. 

The  tools  carried  by  the  men  and  in  the  wagons  are 
sufficient,  with  a  few  that  can  be  obtained  in  the  town 
and  neighboring  farms,  inchiding  teams  and  plows.  Men 
will  be  worked  four  hours  per  day. 

The  work  should  be  undertaken  in  the  following 
order:  First  line  trenches,  clearing,  approaches,  shelter 
for  supports  and  reserve,  second  line  trenches,  obstacles, 
splinter-proofs. 

Total  time  recjuired  to  execute  the  work  outlined 
above,  three  days  of  four  hours.  When  this  work  has 
been  completed,  small  working  parties  will  be  employed 
each  day  to  extend  the  clearing  of  the  foreground,  im- 
prove the  concealment  of  the  trenches,  strengthen  the 
obstacles,  and  increase  the  protection  for  the  supports 
and  reserve. 


127 


FULB  PHOBLXM  N^3 


Seals:  3  Inches -IMib 


I 


127 


APPENDIX. 

The  following  extracts  from  General  Orders  of 
the  War  Department  give  the  tools  carried  by  the 
different  arms,  which  could  be  used  for  intrenching  : 

Intrenching  tools  carried  by  a  company  of  infan- 
try, G.  O.  No.  23,  1906: 

yi,  ft.  folding  rule  4  hand  axes 

15  pick  mattocks  3  wire  cutters 

45  intrenching  shovels 

The  following  engineer  equipment  is  furnished 

each  company  of  infantry  to  be  carried  in  the  extra 

regimental  wagon,  G.  O.  No   221,  1907: 

Augur,  i-inch i         Nails,  assorted,  pounds 10 

Axes    6        Pliers,  wire  cutting 7 

Crowbar,  12  pounds i         Rule,  2-foot. i 

Hatchets 6  Saw,  hand,  crosscut,  with  sheath .     i 

Matchetes  with  sheaths  ....  20  Rope,  2>^-inch,  feet. ......  .250 

The  following  engineer  equipment  is  furnished 
the  cavalry,  to  be  carried  on  pack  animals,  G.  O.  No. 
221,  1907  : 

To  each  troop  : 

Augur,  I -inch i  Pick  mattocks,  large 5 

Axes,  6-pound 4  Pliers,  wire  cutting 6 

Crowbar   i  Rules,  2-foot 2 

Hatchets    4  Saw,  crosscut  with  sheath ...  i 

Nails,  assorted,  pounds 5  Shovels,  large 15 

PACK  DEMOLITION  OUTFIT. 
To  each  squadron  : 

Box,  match,  tin .... , i  Fuse,  instantaneous,  feet .  .  .   200 

Caps,  detonating 100  Hammers,  drilling,  7  pound .      2 

Chisels,  cold,  j^-pound i  Hammer,  engineer's,  3  pound 

Crowbars  2  Pliers,  nose  cutting 

Drills,  double  bitted 2  Shoes,  mule,  sets 

Explosive,  pounds 50  Spoon,  drilling 

Fuse,  Bickford,  feet 200  Wrench,  monkey 


128 


Allowance  of  tools  for  field  service,  G.  O.  No.  95, 
1908: 


Hegimetital 

Headquarters. 

Infantry 

Axes 10 

Hatchets.  ......  10 

Pickaxes 3 

Spades 3 

A  rtillery 

Axes 6 

Hatchets    6 

Pickaxes i 

Spades i 

Cavalry 

Axes 6 

Hatchets  6 

Pickaxes i 

Spades i 


Battalion 
Hdqrs. 


Sq.  Hdqrs. 
2 


Band. 


M.  O.  P. 


Company, 


6 
6 
4 
4 
Battery 
3 
3 
7 
7 
Troop 
6 
6 
4 
4 


Total  in 
Regiment. 


96 
96 

58 
58 

32 

32 

48 
48 

92 
92 
56 
56 


In  addition  to  the  above,  each  escort  wagon  carries 
one  axe,  one  pickaxe,  and  one  spade.  The  allowance 
of  escort  wagons,  as  follows  : 

Regiment 
Infantry 23 

Artilllery 23 

Cavalry 34 


Battalion 
6 

Company 

I 

lO 

Battery 
3 

Squadron 
10 

Troop 

3 

INDEX 


A 

Paragraph 

Abatis 59 

Access  to  emplacements 70 

Accommodation,  magazine 51 

Advanced  method  of  conducting  field  problems 122 

Advanced  positions 8,  55 

Advanced  trenches , .  53-55 

All-around  attack 90 

Ammunition,  artillery,  expense  magazines  for 69 

Ammunition,  artillery  and  rifle,  storage 51 

Angle  of  departure  and  fall  of  shrapnel 68 

Approaches 12,  49,  55 

Area  of  overhead  cover 49 

Armament 29 

Arrangements  for  fire  to  the  rear   48 

Arthur,  Port,  location  of  batteries  at 65 

Arthur,  Port,  loophole  cover  used  at 46,  110 

Arthur,  Port,  Russian  observing  station  at 71,  115 

Arthur,  Port,  strength  of  garrison 85 

Artillery  ammunition,  storage 51 

Artillery,  disposition  of 27 

Artillery,  effect  of 13,  44,  4a,  46,  56,  60,  61 

Artillery,  enemy  unprovided  with 92 

Artillery  expense  magazines 69 

Artillery  fire,  protection  of  supports  from 56 

Artillery  fire,  trenches  to  be  screened  from 63 

Artillery  fire,  indirect 35,  68 

Artillery,  flash  defilade 65 

Artillery,  form  of  emplacement  for 66 

Artillery,  gun  pit 67,  114 

Artillery  in  redouts 42 

Artillery,  location  of 15,  30-34,  65,  67,  68 

Artillery,  maximum  effective  ranges 65 

Artillery,  mobility  of. 28 

Artillery  of  each  section 23 


130 

Paragraph 

Artillery  positions 15,  30-38,  65-73 

Artillery,  position  with  reference  to  infantry 32 

Artillery,  strength  of,  in  a  defensive  position 83 

Artillery,  tactical  employment  of,  in  defense 27-38 

Attack,  all-around 90 

Attack,  counter,  influence  on  strength  of  garrison 78,  80 

Attack,  counter,  placing  of  obstacles  for 59 

Attack,  counter,  second  line  to  assist 9 

Attack,  fortifications  on  the 93-98 

Attack,  night 13.  74 

Auxiliary  means  of  defense , 74-77 


B 

Background. 47,  63 

Balloons,  captive 6,  72 

Batteries,  location  of  at  Port  Arthur 65 

Battery,  siege 66 

Battlefield,  fortifications  on  the 94 

Battlefield,  organization  of  a  defensive 10 

Bombproots 49,  56 

Buildings 60,  61 

Bullet,  penetration  of  rifle,  machine  gun  and  shrapnel 44 


Calculation  of  men  and  time  to  execute  defensive  works 99-117 

Camp,  intrenched 6 

Capacity  of  men  for  digging .         99 

Captive  ballons 6,  72 

Character,  general,  of  supporting  points 41 

Classes  of  defensive  positions 5 

Clearing  of  the  foreground 60 

Combination  of  works  for  command 23 

Command 18 

Command  of  parapet 45,  63 

Command,  low  for  artillery 65 

Commander,  section,  telephone  communication  with 58 

Communicating  trench 55,  113 

Communications 13,  14,  20,  40,  49,  53,  55,  75 

Communications,  interior 13,  75 

Communications,  telegraphic  and  telephonic 13,  58,  76 


131 

Paragraph 

Communications  with  the  rear 55 

Concealment 14,  40,  63 

Concealment  of  artillery  positions 65-67 

Concealment  of  communicating  trenches 55 

Concealment  of  the  interior  of  the  defensive  position 17 

Conditions  that  a  good  profile  should  satisfy 45 

Conditions  that  splinter-proofs  should  satisfy 49 

Conditions  to  be  sought  in  laying  out  trenches 14 

Conditions  to  which  every  defensive  position  should  conform.         10 

Connection  between  fortification  and  tactics 2 

Considerations  determining  strength  of  garrison 78 

Contours,  works  to  follow   41 

Counter  attacks,  influence  on  strength  of  garrison 78,  80 

Counter  attacks,  placing  of  obstacles  for 59 

Counter  attacks,  second  line  to  assist 9 

Course  in  field  problems  in  fortication 119 

Cover  for  supports 56 

Cover,  head 46 

Cover,  loophole 46,  108,   110 

Cover,  overhead 49,  52,  56,  66,  73,  109,  111,  112 

Cover  trenches 56 

Crest,  interior,  height  of 45,  63 

Crest,  interior,  no  breaks  in   49 

Crest,  military 53 

Crest,  sky-line 63,  65 

Cross  fire 65 


D 

Dead  spaces 65 

Defense,  auxiliary  means  of 74-77 

Defense,  number  of  men  per  yard 78-85 

Defense  of  small  isolated  posts  occupied  by  detachments 86-92 

Defense,  tactical  employment  of  artillery  in 27-38 

Defense,  tactical  organization  of  infantry  in 22-26 

Defensive  field  of  battle,  organization  of 10 

Defensive  position,  classes 5 

Defensive  position,  concealment  of  interior 17 

Defensive  position,  conditions  to  which  every,  should  conform         10 

Defensive  position,  examples  of  garrison  of 85 

Defensive  position,  garrison  of 78-85 

Defensive  position  in  woods 62 


132 

Paragraph 

Defensive  position,  number  of  men  per  yard 78-85 

Defensive  position,  strength  of  artillery 83 

Defensive  position,  strength  of  engineers 83 

Defensive  position,  strength  of  general  reserve    84 

Defensive  position,  strength  of  infantry ; 82 

Defensive  works,  calculation  of  men  and  time  to  execute 99-117 

Defensive  works,  drainage 57 

Defilade,  flash,  for  artillery 65 

Defilade  of  roads 75 

Demolition  of  houses  and  buildings 60 

Departure,  angle  and  slope  of,  for  shrapnel 68 

Design  of  works 1 ,  39-64 

Detachments,  defense  of  small  isolated  posts  occupied  by.  .  .  .  86-92 

Determination  of  strength  of  garrison 78-85 

Discussion  of  field  problems  in  fortification 1 19,  122 

Dispersion  of  guns 31 

Dispersion  of  works 13 

Disposition  of  artillery 27 

Distance  of  defensive  line  from  nucleus 6 

Distance  of  obstacles  from  works 59 

Distance  of  overhead  cover  from  firing  trench ,  49 

Ditchers,  traction 101 

Ditches 45 

Division  into  sections 22 

Double  gangs 100 

Drainage  of  defensive  works 57 

Dummy  trenches  or  parapets 64 


E 

Effect  of  weapons 13.  44,  46,  56,  60,  61 

Elbow  rest ...         45 

Electric  searchlights 74 

Emplacements  for  artillery,  design  of 66,  67,  1 14 

Emplacements  for  artillery,  location  of 30 

Emplacements  for  machine  guns 73, 116 

Emplacements,  means  of  access  to 70 

Employment  of  artillery,  tactical 27-38 

Enemy  uncivilized  or  unprovided  with  artillery 92 

Engineer  Field  Manual,  referred  to 

42,  44,  46,  49,  59,  66,  92,  96,  98.  99,  102,  117,  121 
Engineers,  strength  of,  in  a  defensive  position 83 


133 

Paragraph 

Engineers,  technical  parts  of  fortification  assigned  to 2 

Entanglement,  high  wire 59 

Expense  magazine 69 

Explosive  shells,  high,  effect  of 13,  44,  60,  61 

Exterior  slope  of  parapet 45,  63 


F 

Fall,  angle  and  slope  of,  for  shrapnel 68 

Field  guns 15,  37,  67,  68 

Field  guns,  maximum  effective  range 65 

Field  of  battle,  organization  of  defensive 10 

Field  of  battle,  intrenchments  on  the  offensive 93-98 

Field  of  fire 14.  54 

Fire,  cross 65 

Fire,  flank 40 

Fire,  frontal 40 

Fire,  grazing 53 

Fire,  high  angle 15 

Fire,  indirect 15,  35,  68 

Fire,  oblique  or  enfilade 52 

Fire  to  the  rear,  arrangements  for 48 

First  line,  strength  of 23 

Flanks  of  a  defensive  line 7 

Flash  defilade  for  artillery 65 

Foreground,  clearing 60 

Foreground,  covering 54 

Form  of  emplacement  for  artillery 66,  67 

Form  of  supporting  points • 13 

Forts 47.  89 

Fortification,  field  problems  in 118-124 

Fortification,  importance  of 4 

Fortification  on  the  battlefield 94 

Fortification  on  the  offensive 93-98 

Fortification,  relation  to  tactics 2 

Fortification,  tactical  aspect  of 3 

Fortified  line  of  belt  type 13 

Fort  Riley  redout 42,  44,  102 


134 
G 

Paragraph 

Gangs,  double 100 

Garrison  of  points  of  support  of  second  line 25 

Garrison,  strength  of,  for  defensive  work 78-85 

General  character  of  supporting  points 41 

General  instructions  for  course  in  field  problems 121 

General  objects  to  be  aimed  at  in  preparing  an  area  for  defense         40 

General  principles  of  fortification 1-21 

General  reserve 26,  84 

Gorge 47 

Gorge  trench 48 

Grazing  fire 53 

Gun  pit    67,  114 

Guns,  dispersion  of 31 

Guns,  field   15,  37,  65,  67,  68 

Guns,  indirect  fire  for   15,  35,  68 

Guns,  location  of 33 

Guns,  machine '68,  73,  116 

Guns,  position  for  light 67 

Guns,  proportion  of,  to  howitzers 29 

Guns,  ranges  of  field  and  siege  .- 65 

Guns,  rapid  fire 36 

Guns,  siege ...  29,  65,  66 


H 

Hamiliton,  General  Ian,  extracts  from  "  Staff  Officer's  Scrap 

Book" 18,  46 

Hasty  intrenchments 79,  93,  97 

Head  cover 46,  108-111 

Heavy  artillery,  location  of  emplacements  for 30 

High  angle  fire 15 

High  explosive  shells,  effect  of 13,  44,  60,  61 

High  wire  entanglement 59 

Hill,  location  of  works  on 18,  53 

Houses..  .  . 60,  61 

Howitzers,  location  of 34 

Howitzers,  proportion  of,  to  guns 29 

Howitzers,  ranges  of  siege 65 


135 

I 

Paragraph 

Importance  of  fortification 4 

Indirect  fire 15,  35,  68 

In-antry,  position  of  artillery  with  reference  to 32 

Infantry,  precedence  of  16 

Infantry,  strength  of  in  a  defensive  position 82 

Infantry,  tactical  organization  of,  in  defense 22-26 

Infantry,  works,  design  of 39-64 

Instructions  for  course  in  field  problems 121 

Interior  communications 75 

Interior  of  defended  position,  concealment  of 17 

Interior  slope  c  f  parapet 45 

Intervals  between  supporting  points 11 

Intrenched  camp .  6 

Intrenchments 43,  45,  105-113 

Intrenchments,  garrison  of  hasty 79 

Intrenchments,  hasty 79,  93-97 

Intrenchments,  tactical 97 

Invisibility 14,  63,  65 

Isolated  posts  occupied  by  detachments,  defense  of 86-92 


J 

Japanese  gun  positions 15,  65 

Japanese  lines  north  of  Mukden 50,  73 

Japanese  machine  gun  emplacement , 73 

Japanese  profiles 45, 107 

Japanese  redout 42, 104 

Japanese  use  of  intrenchments  on  offensive 97 

Judson,  Major  W.  V.,  extracts  from  report  of 13,  63 


K 

Kneeling  trench 45,  97 

Kuhn,  Major  J.  E.,  extracts  from  report  of 

5,  15,  18,  42,  45,  46,  49,  63,  65,  97 
Kuropatkin,  General,  comments  on  use  of  hasty  intrenchments         97 


136 
L 

Paragraph 

Laying  out  trenches,  conditions  to  be  sought 14 

Length  of  trenches 13,  52 

Liaoyang 63,  97 

Light  guns 29,  67 

Lighting  of  exterior  slope 63 

Line,  defensive 7 

Line,  defensive,  distance  of  from  nucleus 6 

Line,  first,  strength  of 23 

Line  of  approach 12 

Line  of  retreat 21 

Line  of  trench,  location 18,  53 

Line,  second. 6,  19,  25 

Line,  sky 47,  53,  65 

Location  of  artillery 15,.  30,  33,  34,  65 

Location  of  depots  of  ammunition  and  supply 13 

Location  of  fortifications  on  the  offensive 96 

Location  of  guns 33 

Location  of  howitzers  and  mortars 34 

Location  of  obstacles 59 

Location  of  overhead  cover 47 

Location  of  roads 13 

Location  of  supports 56 

Location  of  reserves 13,  26 

Location  of  trenches 18,  53,  54 

Location  of  works  in  second  line 19 

Lookouts 50 

Loophole  cover 110 

Loopholes 46,  108-111 

Lying  down  trench 45 


M 

Machine  gun  emplacement 73,  116 

Machine  gun  bullets,  penetration 44 

Machine  guns 38 

Magazine  accommodation 51 

Magazines,  expense 69 

Man,  capacity  of  average  untrained  for  digging 99 

Map,  solution  of  field  problems  on 123,  124 

Maximum  effective  ranges  of  field  and  siege  guns 65 


137 

Paragraph 

Means  of  access  to  emplacements 70 

Means  of  communication 20 

Means  of  defense,  auxiliary 74-77 

Men  per  yard,  number  of 13,  45,  78-82.  85 

Men  required  to  execute  defensive  works 99-117 

Military  crest 53 

Mobility  of  artillery 28 

Mobility  of  reserve 26 

Morrison,  Major  J.  F.,  extracts  from  report  of 4,  97 

Mortars,  location  of 34 

Mortars,  range  of  siege 65 


Nanshan  Hill 63,  85 

Night  attacks  and  marches 13,  74 

Notched  parapet 46 

Nucleus,  distance  from  defensive  line ....  6 

Number  of  men  per  yard  in  defensive  positions 13,  45,  78-82,  85 

O 

Observing  station 71,  115 

Obstacles 54,  59,  92 

Offensive,  fortifications  on  the 93-98 

Operations,  siege 98 

Organization  of  a  defensive  field  of  battle 10 

Organization,  tactical,  of  infantry  in  defense 22-26 

Overhead  cover 49,  52,  56,  66,  73,  109,  111,  112 


Parados    47 

Parapet,  dummy 64 

Parapet,  exterior  slope  of 45,  63 

Parapet,  interior  slope 45 

Parapet,  no  projections  above 49 

Parapet,  notched 46,  109 

Parapet,  relief  of 45,  63 

Parapet,  thickness  of 45 

Penetration  of  rifle,  machine  gun  and  shrapnel  bullets 44 

Percussion  shrapnel  . .             44 


138 

Paragraph 

Pit,  gun 67,  114 

Pit,  machine  gun 73, 116 

Pit,  seepage 57 

Plevna 85 

Points,  supporting,  form  of 13 

Points,  supporting,  general  character  of 41 

Points,  supporting,  intervals  between 11 

Points,  supporting,  of  second  line,  garrison 25 

Pom-poms 36,  74 

Port  Arthur,  garrison  of 85 

Port  Arthur,  location  of  batteries  at 65 

Port  Arthur,  loophole  cover  used  at 46,  110 

Port  Arthur,  observing  station  at 71,  115 

Port  Arthur.  Russian  trench  at 45 

Position,  artillery,  dispersion  of  guns  in. 31 

Position  of  artillery  with  reference  to  infantry 32 

Position  of  section  reserve 24 

Positions,  advanced 8,  55 

Positions,  artillery 15,  30-38,  65-73 

Positions,  defensive,  classes  of 5 

Positions,  defensive,  examples  of  garrison  of 85 

Positions,  defensive,  garrison  of 78-85 

Positions,  defensive,  in  woods 62 

Positions,  defensive,  strength  of  artillery 83 

Positions,  defensive,  strength  of  general  reserve 84 

Positions,  defensive,  strength  of  infantry 82 

Positions  for  light  guns 67 

Posts,  defense  of  small  isolated,  by  detachments  86-92 

Precedence  of  infantry 16 

Problems,  field,  in  fortification 118-124 

Profiles 43,  45,  63 

Profiles,  men  and  time  required  to  execute 105-109 

Proportion  of  guns  to  howitzers 29 

Pumping  for  drainage 57 

R 

Railroad 13,  75 

Range,  long,  mid,  short 54 

Ranges  of  field  and  siege  guns 65 

Rapid-fire  guns 36,  67 

Rear,  arrangements  for  fire  to  the 48 


139 

Paragraph 

Rear,  communication  with  the 55 

Redouts 13,  42,  44,  47,  48,  89,  102-104 

Reichmann,  Major  Carl,  extracts  from  report  of 4,  45,  56 

Relation  of  fortification  to  tactics 2 

Relief  of  parapet 45 

Reserve,  general 26,  84 

Reserve,  section 24 

Reserves  on  reverse  slopes ...         68 

Reserves,  shelter  for 90 

Reserves,  strength  of 23,  84 

Rest,  elbow 45 

Retired  trenches 53 

Retreat,  lines  of 21 

Reverse  slopes 56,  68 

Ricochet 44 

Ridge,  location  of  trenches  on ]  8,  53 

Rifle,  ammunition,  storage 51 

Rifle  bullets,  penetration 44 

Riley,  Fort,  redout   42,  44,  102 

Roads 12,  13,  75 

Russian  batteries  at  Port  Arthur 65 

Russian  dummy  parapets 64 

Russian  observing  station 71,  115 

Russian  redout 42,  103 

Russian  trench  at  Port  Arthur 45,  108 


Sandbags  for  head  cover 46 

San  Juan,  Cuba 85 

Screens 63 

Searchlights,  electric 74 

Second  line 6,  9,  19,  25 

Section  reserve,  position  of 24 

Sections,  artillery  of 23 

Sections,  division  into 22 

Seepage  pits 57 

Sha  River,  use  of  hasty  intrenchments  at 97 

Shells,  high  explosive,  effect  of 13,  44,  60,  61 

Shelter  for  reserves 90 

Shelter  for  supports 56 

Shelters,  overhead 49,  52,  56,  66,  109,  111,  112 


140 

Paragraph 

Shields,  protection  for  guns  with 67 

Shrapnel,  angle  and  slope  of  departure  and  fall 68 

Shrapnel,  effect  of 13,  44,  45,  56 

Siege  battery 66 

Siege  guns,  maximum  effective  range 65 

Siege  operations 98 

Sight,  nucleus  to  be  kept  out  of,  from  enemy's  position 6 

Situation,  tactical,  of  works 10 

Sky-line 47,53,65 

Slashings 59 

Slope,  exterior  of  parapet  45,  63 

Slope,  of  departure  and  fall  of  shi'apnel 68 

Slope,  reverse 56,  68 

Slope,  trenches  at  foot  of 53,  55 

Small  isolated  posts  occupied  by  detachments,  defense  of  . .  .  86,  92 

Solution  of  field  problems  on  map 123-124 

Splinter  proofs 49,  52,  56,  66,  109,  111,  112 

Staff  Class  course  in  field  problems  in  fortification 119 

Standing  trenches 45,  105-109 

Station,  observing 71,  115 

Strength  of  artillery  in  a  defensive  position 83 

Strength  of  engineers  in  a  defensive  position 83 

Strength  of  first  hne,  supports  and  reserves 23 

Strength  of  garrison  of  a  defensive  position 78-85 

Strength  of  general  reserve  of  a  defensive  position 84 

Strength  of  infantry  of  a  defensive  position 82 

Supporting  points,  form  of 13 

Supporting  points,  general  character  of     41 

Supporting  points,  interval  between   11 

Supply,  water 77,  90 

Supports,  cover  for 56 

Supports,  on  reverse  slopes 68 

Supports,  position  of 55 

Supports,  strength  of 23 

Supports,  telephone  communication  with 58 


T 

Table  for  indirect  fire 68 

Table  giving  time  and  men  required  to  execute  different  work       117 

Tactical  aspect  of  fortifications 3 

Tactical  employment  of  artillery  in  defense 27-38 


141 

Paragraph 

Tactical  organization  of  infantry  in  defense 22-26 

Tactical  situation  of  works 10 

Tactics,  relation  of,  to  fortification 2 

Target,  works  arranged  to  offer  shallow 40 

Tasks 99 

Telegraphic  communication 76 

Telephonic  communication 13,  24,  31 ,  58,  76 

Thickness  of  overhead  cover .  .    .         49 

Thickness  of  parapet 45 

Timber  on  hillsides,  location  of  trench  in 53 

Time  required  to  execute  defensive  works 99-117 

Traction  ditchers 101 

Traverses 45,  52,  66,  108 

Trench,  advanced 53,  54 

Trench,  arrangement  of,  for  fire  to  the  rear . 48 

Trench,  communicating 55,  113 

Trench,  distance  of  obstacles  from 59 

Trench,  dummy 64 

Trench,  firing 45,  105-112 

Trench,  lying,  kneeling,  standing 45,  105-112 

Trench,  retired 53,  54 

Trenches,  cover 56 

Trenches,  drainage  of 57 

Trenches,  length  of 13,  52 

Trenches,  location  of 18,  19,  53,  54 

Trenches,  telephone  communication  with 58 

Triangular  profile 45,  106 

Type  designs 1 


U 

Uncivilized  enemy 92 

V 

Value  of  field  problems  in  fortification 120 

Villages 01 


142 
W 

Paragraph 

Walls 61 

Water  supply 77,  90- 

Weapons,  effect  of 44 

Wells 77 

Wire  entanglement,  high 59 

Woods 53,  62 

Wooded  country,  use  of  abatis  and  slashings  in 59 

Works,  arrangement  of 40 

Works,  calculation  of  time  and  men  to  construct 99-117 

Works,  combination  of,  for  command 23 

Works,  design  of 1.  39-64 

Works,  distance  of  obstacles  from 59 

Works,  drainage  of 57 

Works,  infantry,  design  of 39-64 

Works,  intervals  between 11 

Works,  location  of 18,  19,  53 

Works,  tactical  situation  of 10 


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